prediction of leachate generation from

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University of Cape Town PREDICTION OF LEACHATE GENERATION FROM MINERALS PROCESSING WASTE DEPOSITS by Graham Mark Davies Dissertation submitted to the University. of Cape Town in fulfilment of the requirements for the degree of Master of Science in Engineering Department of Chemical Engineering University of Cape Town Rondebosch 7700. September 1995

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PREDICTION OF LEACHATE GENERATION

FROM

MINERALS PROCESSING WASTE DEPOSITS

by

Graham Mark Davies

Dissertation submitted to the University. of Cape Town in fulfilment of the requirements for the degree of

Master of Science in Engineering

Department of Chemical Engineering University of Cape Town Rondebosch 7700.

September 1995

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The copyright of this thesis vests in the author. No quotation from it or information derived from it is to be published without full acknowledgement of the source. The thesis is to be used for private study or non-commercial research purposes only.

Published by the University of Cape Town (UCT) in terms of the non-exclusive license granted to UCT by the author.

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Synopsis.

The minerals processing industry in South Africa produces significant tonnages of waste material which are disposed of commonly in dedicated waste depositories. These deposits pose a potential to pollute the environment if leachate is generated within the deposit and released to the surroundings. Leachate generation is generally investigated using laboratory columnar experiments which attempt to mimic the physical and chemical processes which occur in the deposit. These experiments, termed lysimeter experiments,

. are time consuming in that they typically last for at least a few months and can last for up to three years. Lysimeter experiments are also costly to conduct. Because of restrictions such as these, relatively few deposits have been characterised to determine the leachate which they generate and thus the risk which they pose to the environment.

There is an urgent need to be able to estimate the environmental risks associated with existing waste deposits. The first step towards assessing this risk would be an ability to predict leachate generation within a specific deposit. Such an ability could be used to identify which of the existing deposits produce significant leachate and thus pose a potential hazard to the environment. Equally, if leachate generation from new deposits could be estimated as a function of waste material and characteristics of the waste deposit, this information could be used to improve the engineering design of waste deposits.

The work presented in this thesis involved identifying suitable modelling strategies which could be used to determine leachate generation within waste deposits which contain waste material typical of that produced by the minerals processing industry. Two modelling strategies have been investigated. The first modelling strategy involved a

macroscopic model in which all effects such as intrinsic chemical kinetics, intra-particle diffusion, external mass transfer and hydrodynamic considerations are lumped into a single parameter. The result of this approach is an effective reaction rate for the release . of hazardous constituents from a volume element of the waste deposit. The effective reaction rate is determined by fitting the model to experimental data base9 on lysimeter tests. The main advantage of this model is that it eliminates the need for a detailed understanding of the individual factors which contribute to leachate generation. This model was investigated both for its inherent simplicity and for use in cases where insufficient information with respect to the intrinsic chemical reaction rates, intra-particle diffusion, external mass transfer or hydrodynamic aspects exist. The main disadvantage of this model is that it has a limited predictive ability in that the individual significance of any one factor which contributes to leachate generation cannot be determined. For this reason a second, more detailed model, termed the heterogenous columnar model, has also been investigated.

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The heterogenous columnar model describes the release of hazardous constituents at the

single particle level and relates this information to the overall leachate generation within

the deposit. This is achieved by calculating the release of hazardous constituents from

the size distribution of particles to the bulk fluid between these particles. The release

of hazardous constituents from individual particles is determined by making use of a

particle-scale chemical reaction 'model. This particle-scale model is sufficiently detailed

to be able to determine the relative contribution to the overall release of hazardous

constituents from the particles of intrinsic chemical kinetics of the reactions to the effects

of diffusion of the fluid reagent into each particle. The heterogenous columnar model

can also be used to determine whether the effective rate of release of hazardous

constituents from the particles (which include intrinsic kinetic and diffusional

contributions) or the flow of fluid reagent through the deposit limits the release of

hazardous constituents from the deposit. This information can be used to determine the

main factors which affect the release of hazardous constituents from waste deposits and

can thus be used to improve the design of waste deposits.

Probably the most important attribute of the heterogenous columnar model is that

methods have been investigated to determine the model parameters from a simple

continuously stirred tank reactor (CSTR) type experiment.

The ability of the heterogenous columnar. model to predict leaching behaviour has been

investigated using data on precious metal leaching found in the literature. The results

are encouraging in that the model can accurately predict the leaching behaviour of

precious metals. A preliminary investigation into determining suitable particle-scale

model parameters for a sample of waste from a CSTR experiment has been conducted.

This too has yielded encouraging results. However, the application of using the

heterogenous columnar model using these parameters to describe leachate generation

within waste deposits or lysimeter experiments still needs to be demonstrated. Once the

heterogenous columnar model has been verified against data pertaining to leachate

generation from a waste deposit it may start to provide the minerals processing industry

with the information which it so desperately requires in order to dispose of wastes in a

manner which minimises the impact on the environment.

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Acknowledgements.

I would like to thank Dr J. G. Petrie for his guidance and assistance in this work. I believe that no graduate student can learn to do research effectively on their own and I am grateful for what I have learnt from Dr Petrie. In particular Dr Petrie has taught me the level of rigour required in research and the ability to constructively question any results obtained to determine their significance and accuracy. In addition to this, working under Dr Petrie I have become aware of the pressing environmental issues facing the chemical and minerals processing industries in South Africa. I believe that such an awareness will be invaluable to me as a chemical engineer.

I am also grateful for having had the opportunity to work in the 'Greenhouse' in the Department of Chemical Engineering at the University of Cape Town. Working with such a diverse and talented -group of people has been most stimulating and has kept me on my toes. The weekend away at Wilderness, the mini investigation into possible methods to clean up oil on the beaches and the commissioning of the 'fish tank' are only a few of the many things which made working in the group so interesting.

Last, but not least, I wish to gratefully acknowledge the financial assistance of MINTEK. Without this assistance this project would not have been possible.

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Table of Contents.

Synopsis.

Acknowledgements.

Table of Contents.

List of Tables.

List of Figures.

Nomenclature.

1. Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1.1 Statement of the Objectives. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

1.2 Research Methodology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

1.3 Thesis Layout. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

2. Relevant Considerations when Modelling Leachate Generation and Mobility. 7

2.1 Particulate and Hydrodynamic Considerations. . . . . . . . . . . . . . . . . 7

2.1.1 Particulate Considerations. 7

2.1.2 Hydrodynamic Considerations. 9

2.2 Review of Existing Leachate Generation and Mobility Models. 14 -

2.2.1 Empirical Models. . . . . . . . . . . . . . . . . . . . . . . . . . . 14

2.2.2 Models which make use of the Continuity Equation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

2.2.3 Models Suitable for Predicting Leachate Generation from Solidified Monolithic Structures. . . . . . . . . . . . . 18

2.2.4 Models Describing Contaminant Migration away from Deposits. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

2.3 Summary of the Strategy Adopted in Precious Metal Heap Leaching Models. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

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2.4 Modelling the Release of Hazardous Constituents from Partially Saturated Granular Waste Deposits. . . . . . . . . . . . . . . . . . . . . . . . 25

3. A Macroscopic, Lumped Parameter Model to Describe Leachate Generation and Mobility in Granular Waste Deposits. • •...•••••••.•.. ·• • • • • • • • . • • 29

3.1 Development of the Equations. . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

3.2 Expressing the Equations in Dimensionless Form. . . . . . . . . . . . . . 33

3.3 Solution Strategy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

3.4 Introduction _ of a Variable Fluid Velocity into the Solution Strategy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

3.5 Suitable Computer Routines for the Model. . . . . . . . . . . . . . . . . . . 37

3.6 Verification of the Computer Routines. . . . . . . . . . . . . . . . . . . . . . 38

3. 7 Results and Discussion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

3. 7 .1 General Behaviour. . . . . . . . . . . . . . . . . . . . . . . . . . . 41

3.7.2 Effect of Competing Reactions. . . . . . . . . . . . . . . . . . 44

3.8 Fitting the Model to Lysimeter Experiments. . . . . . . . . . . . . . . . . . 49

3.8.1 Model Requirements. . . . . . . . . . . . . . . . . . . . . . . . . 49

3.8.2 Fitted parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . 50

3.9 Limitations of the Model. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

4. A Summary of the Chemical Reaction Model Applicable to Single Particles as Developed by Dixon [1992]. . . . • . . . . . . • . • . . . . • . . . . . . . . . . . . . . . . . 52

4.1 Development of the Equations. . .................... ~ . . . . . 52

4.2 Expressing the Equations in Dimensionless Form. . . . . . . . . . . . . . 55

4.3 Suitability of Dixon's Model to Hazardous Constituent Leaching From Waste Particles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

4.4 Solution Strategy. . ....................... : . . . . . . . . . . . . 57

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4.5 Suitable Computer Routines for the Model. . . . . . . . . . . . . . . . . . . 59

4.6 Verification of the Computer Routines. . . . . . . . . . . . . . . . . . . . . . 60

4.7 Application pf the Model. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

5. A Model to Describe Leachate Generation from Granular Wastes in a Continuously Stirred Tank Reactor Experiment. . . . . . • . . . . . • . . . • . . • . 66

5 .1 Development of the Mass Balance Equation for the Bulk Fluid Reagent in a CSTR which Contains Equi-Sized Particles. . . . . . . . . 66

5.2 Model Parameters as a Function of Particle Size. . . . . . . . . . . . . . . 68

5.2.1 Determination of the Model Parameters Applicable to Precious Metal Leaching with Respect to a Reference Size Class of Particles. . . . . . . . . . . . . . . . 68

5.2.2 Determination of the Model Parameters Applicable to Leaching of Hazardous Constituents from Waste Particles with Respect to a Reference Size Class of Particles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

5. 3 Extension of the Bulk Fluid Mass Balance Equation to Incorporate Fluid Reactant Consumption from a Size Distribution of Particles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

5.4 Solution Strategy: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

5.5 Suitable Computer Routines for the CSTR Model. . . . . . . . . . . . . . 73

5.6 Verification of the Computer Routines. . . . . . . . . . . . . . . . . . . . . . 74

5. 7 Results and Discussion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

5. 7.1 General Behaviour. . . . . . . . . . . . . . . . . . . . . . . . . . . 76

5. 7. 2 Effect of Particle Size Distribution on the Fractional Conversion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

5. 7. 3 Effect of the Location of Hazardous Constituents on the Fractional Conversion. . . . . . . . . . . . . . . . . . . . . 83

5.8 Fitting the Model to CSTR Results. . . . . . . . . . . . . . . . . . . . . . . . . 85

5.8.1 Model Requirements. . . . . . . . . . . . . . . . . . . . . . . . . 86

5.8.2 Fitted Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . 86

/

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5.9 Applications and Limitations of the Model. . . . . . . . . . . . . . . . . . . 87

5.9.1 Applications of the model. . . . . . . . . . . . . . . . . . . . . 87

5.9.2 Limitations of the model. . . . . . . . . . . . . . . . . . . . . . 87

6. A Microscopic, Columnar Model to Describe Leachate Generation and Mobility in Granular Waste Deposits. • • • • • • • • • • • • • • • • • • • • • • • • • • • 89

6.1 A Modelling Strategy based on Heap Leaching Models. . . . . . . . . . 90

6.2 A Modelling Strategy based on a Rigorous Mathematical Approach. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92

6.3 Inclusion of a Global Wetting Factor into the Solution Strategy. 96

6.4 Suitable Computer Routines for the Heterogenous Columnar Model. ............................................. 97

6.5 Verification of the Computer Routines. . . . . . . . . . . . . . . . . . . . . . 99

6.6 Determination of the Heterogenous Columnar Model Parameters from Appropriate CSTR type Experiments. . . . . . . . . . . . . . . . . . . 103

6. 7 A Summary of the Experimental Data which is Required to Verify the Applicability of the Heterogenous Columnar Model to describe the Leaching of Hazardous Constituents from Waste Deposits ..... 105

7. Summary of the Applications, Limitations and Extensions of the Heterogenous, Columnar Model. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110

7 .1 Comparison of the Heterogenous Columnar Model to the Model of Roman et al. [1974] and the Columnar Model of Dixon [1992, 1993] ............................................... 110

7.1.1 Comparison to the Model of Roman et al. [1974] .... 112

7.1.2 Comparison to the Columnar Model of Dixon [1992, 1993] ..................................... 113

7 .2 A Summary of the Potential Engineering Applications of the Heterogenous Columnar Model. .......................... 114

7.2.1 Improved Deposit Design based on Results from the Heterogenous Columnar Model. . . . . . . . . . . . . . . . 114

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7. 2. 2 Using the Heterogenous Columnar Model to Choose Upstream Processes which would Result in More Stable Wastes. . ............................ 116

7.2.3 . Using the Heterogenous Columnar Model to Asses the Risks and Liabilities Associated with Existing Waste Deposits. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

7. 3 · Limitations and Possible Extensions of the Heterogenous Columnar Model. . ............................................ 117

7.3.1 Incorporation of External Mass Transfer Resistances into the Model. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

7.3.2 Inclusion of Intra-Particle Dissolved Species Transport Resistances into the Model. . . . . . . . . . . . . 119

7.3.3 Inclusion of Matrix Dissolution and Hazardous Constituent Re-Precipitation in the Heterogenous Columnar Model. . . . . . . . . . . . . . . . . . . . . . . . . . . . 120

7.3.4 Inclusion of More Realistic HydrodynamiC Flow Models into the Heterogenous Columnar Model. . . . . 120

7.4 Statement of the Significance of the Work Presented in this Thesis.

References.

Appendices.

Appendix I.

Appendix IL

Appendix III.

Appendix IV.

. Appendix V.

122

Summary of the Method of Characteristics.

Solution Algorithm and Code for Model4D 1.PAS and Model4D2.PAS.

Solution Algorithm and Code for Model2D2.PAS.

Solution Algorithm and Code for Model5El .PAS and Model5E2. PAS.

Solution Algorithm and Code for Model6Cl.PAS and Model6C2.PAS.

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List of Tables.

2-1. Summary of the Models which can be used to Describe the Release of Hazardous Constituents from Waste Deposits. . . . . . . . . . . . . . . . . . . . . . 15

3-1. Summary of the Parameter Combinations Investigated to Determine the Effect a Buffer Material on Hazardous Constituent Release. . . . . . . . . . . 45

3-2. Summary of Parameters used to Demonstrate Extension of the Model to More than One Reactive Hazardous Constituent. . . . . . . . . . . . . . . . . . . . 48

5-1. Size Distribution and si,k used in the Analysis. . . . . . . . . . . . . . . . . . . . . 76

5-2. Reference Size Class Parameters. (Reference Size Class = Size Class 8.) ............ : . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

5-3. Summary of the Conditions used to Investigate the Effect of Size Distribution on Fractional Conversion. . . . . . . . . . . . . . . . . . . . . . . . . . . . 82

5-4. Summary of the Conditions used to Investigate the Effect of Hazardous Constituent Location on Fractional Conversion. . . . . . . . . . . . . . . . . . . . . 84

6-1. Physical Properties and Operating Conditions. . .................... 100

6-2. Size Distributions. (% Occurrence.) ............................. 101

6-3. Summary of the Conditions in the CSTR Test on a Waste Sample.. . .... 107

6-4. Values of the Fitted Parameters. . .............................. . 108

7-1. Summary of the Properties of the Heterogenous Columnar Model and the Heap I:eaching Models of Roman [1974] and Dixon [1992,1993] ........ 108

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List of Figures.

2-1. Film, rivulet and filament flow patterns as described by Lutran et al. [1991]. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

·2-2. CAT scans used to investigate the flow patterns in a square column packed with equi-sized glass spheres. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

2-3. Layout of a waste form in a landfill. . . . . . . . . . . . . . . ~ . . . . . . . . . . . . . . 13

2-4. Inference of leaching rates following different leaching scenarios. . . . . . . . 20

2-5. An ore heap conceptually divided into columnar sections and the columnar sections divided into disks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

2-6. Summary of the strategy used to determine the breakthrough curve in Heap leaching operations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

2-7. An example of a two dimensional, porous medium model used to simulate the geometrical characteristics of particles in a trickle bed reactor and a typical flow pattern predicted by using the strategy of Zimmerman et al. [1987]. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

3-L Schematic of a lysimeter which forms the basis for the macroscopic, lumped parameter model. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

3-2. Comparison of the predicted flow profile with the analytical profile for a lysimeter in which no chemical reactions take place. . . . . . . . . . . . . . . . . . 38

3-3. Chemical species in the model are interchangeable. . . . . . . . . . . . . . . . . . 40

3-4. Profiles of hazardous constituents which react at the same rate are co-incident. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

3-5. Fluid reagent profiles and solid reactant profiles within a lysimeter predicted by Model4Dl for various parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

3-6. Conversion curves for a lysimeter predicted by Model4Dl for various parameters.. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . 43

3-7. Concentration profiles for two competing reactions. . . . . . . . . . . . . . . . . . 46

3-8. Breakthrough curves for two competing reactions. . . . . . . . . . . . . . . . . . . 47

3-9. Sample printout of concentration profiles for more than one hazardous constituent. . . . . . . . . ; . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

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3-10. Sample printout . of breakthrough curves for more than one hazardous constituent. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

4-1. Schematic diagram of a porous, spherical particle of radius R and a graph showing the concentration gradients within the particle. . . . . . . . . . . . . . . 53

4-2. Concentration profiles predicted by Model2D2 for the parameters as Indicated in the Figure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • . . . . . . . . 61

4-3. The corresponding concentration profiles to Figure 4-2 presented by Dixon. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

4-4. Fraction conversion profiles predicted by Model2D2 for the parameters as Indicated in the Figure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

4-5. The corresponding fractional conversion profiles to Figure 4-4 presented by Dixon. . ................... ·. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

4-6. Fraction conversion profiles as a function of the variable order power predicted by Model2D2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

4-7. The corresponding fractional conversion profiles as a function of variable order power to Figure 4-6 presented by Dixon. . . . . . . . . . . . . . . . . . . . . . 64

5-1. Schematic of a few equi-sized spherical particles submerged in a well stirred beaker of fluid. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

5-2. Summary of the Solution Strategy used in the CSTR model. . . . . . . . . . . . 73

5-3. Concentration profiles predicted by Model5El for a single size class of particles with a large excess of bulk fluid reagent. . . . . . . . . . . . . . . . . . . . 75

5-4. Concentration profiles predicted by Model2D2 using the same parameters used in the simulation used to generate Figure 5-3. . . . . . . . . . . . . . . . . . 75

5-5. Size distribution of particles used in analysis . . . . . . . . . . . . . . . . . . . . . . 77

5-6. Hazardous constituent location data used in the analysis. . . . . . . . . . . . . . 78

5-7. Fluid reagent and solid reactant profiles as a function of particle size. . , . 79

5-8. Overall conversion for the system. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80

5-9. Summary of the size distributions used in the simulations. . . . . . . . . . . . . 82

5-10. Fractional conversion for the size distributions investigated. . . . . . . . . . . . 83

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5-11. Summary of the hazardous constituent location data used in the simulations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

5-12. Fractional conversion for surface hazardous constituents concentrations investigated. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

6-1 Graphical comparison between the macroscopic, lumped parameter model and the heterogenous, columnar model. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

6-2. Summary of the solution strategy used which was based on Roman's solution strategy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

6-3. Solution strategy derived from a rigorous mathematical analysis. . . . . . . . . 96

6-4. Summary of the overall organisation of Program Model6Cl.PAS. . . . . . . . 98

6-5. A typical display produced by Model6Cl.PAS showing the solid and fluid reagent profiles for the smallest, largest and reference size class of particles. . .................................. ; . . . . . . . . . . . . . 99

6-6. Size distribution of the particles in L ysimeter 1. 102

6-7. Size distribution of the particles in Lysimeter 2. 102

6-8. Fitted curve and predicted curve for Model6C 1 compared to the experimental points of Roman [1974]. . ......................... .' 103

6-9. Predicted CSTR conversion versus time curve for O.llof 9.5mm to 13.2mm particles and 1l of 48.8 gp/ of acid ............................... 104

6-10. Concentration of dissolved magnesium in the bulk fluid as a function of timd.07

6-11. Fractional conversion versus dimensionless reaction time. . . . . . . . . . . . . . 108

6-12. Model5El versus CSTR Experimental Data on a Waste Sample. . . . . . . . 109

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Nomenclature.

Roman Letters

DG2. I

DG3. I

E I

~i ~i L M

z

stoichiometry number, kg solid reactant ilkg fluid reagent concentration of reagent A, kg Alm/ concentration of reagent A external to particle, kg Alm[ initial extractable grade of solid reactant i, kg ilkg ore concentration of dissolved species i, kg ilmr 3

bulk concentration of dissolved species i, kg ilm/ grade of solid reactant i within particle, kg i/kg ore initial grade of solid reactant i within particle, kg ilkg ore grade of solid reactant i on particle surface, kg ilkg ore initial grade of solid reactant i on particle surface, kg ilkg ore fraction of the void space within the deposit filled with fluid, dimensionless effective pore diffusivity of reagent A, m[lfI\ s effective pore diffusivity of dissolved species i, m[I~ s ratio of the actual fluid percolation velocity to a reference percolation velocity, dimensionless ratio of the chemical reaction rate i at z=O to the rate of fluid reagent replenishment, dimensionless dimensionless stoichiometric ratio which indicates the fluid reagent strength relative to the solid reactant concentration i within the deposit extraction of dissolved species i, dimensionless rate constant of solid reactant i within particle, kg ilkg ore s[Cp]0 [CA] rate constant of solid reactant ion particle surface, kg i/mP2 s [CJ" [CA] deposit depth, m number of size classes in the size distribution of particles, dimensionless number of solid reactants pellet flow Reynolds number, dimensionless volumetric flow rate of fluid into the deposit, m31s radius, m rate of 'production' of fluid reagent A by reaction with solid species i, kglm2s­particle radius, m time, s reference space time for the deposit, s superficial bulk flow velocity, mi lmh2 s reference fluid velocity (percolation velocity), mis fractional conversion of solid reactant i, dimensionless depth, cm

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•.

"'·

Greek Letters

dimensionless concentration of reagent A dimensionless concentration of reagent A external to particle reagent strength parameter relative to solid reactant i, dimensionless modulus in steady-state model ratio of diffusivity of dissolved species i to reagent A, dimensionless bulk solution volume fraction

€ c01 heap void fraction € 0 ore porosity, cm//cm/ !: dimensionless depth T k ratio of the volume of the particles in size class k to the volume of the

particles in the reference size class, dimensionless

Tl effectiveness factor for solid reactant i, dimensionless e dimensionless flow time Kpi Damkohler II number for solid reactant i within particle, dimensionless Ksi Damkohler II number for solid reactant i on particle surface, dimensionless A.i surface fraction of solid reactant i, dimensionless 11 ratio of volume bulk fluid to fluid in particle pores, dimensionless ~ dimensionless radius Z dimensionless particle radius p0 ore density, g ore/cm3 ore a pi dimensionless grade of solid reactant i within particle asi dimensionless grade of solid reactant i on particle· surface T dimensionless diffusion time T ' dimensionless flow time for the deposit ¢pi reaction ·order for solid reactant i within particle, dimensionless <Psi reaction oredr for solid reactant i on particle surface, dimensionless Xi dimensionless concentration of dissolved species i Xib dimensionless bulk concentration of dissolved species i t ratio of the surface grade of hazardous constituents to the bulk grade of

hazardous constituents within the particle, dimensionless

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Chapter 1. Introduction.

Increasing environmental awareness is challenging both the chemical and minerals processing industries to examine the type and quantity of the waste which they produce, and to critically assess the methods used to dispose of this waste. Presently new technologies are being developed to minimise the overall waste produced. Since the total eradication of wastes is not feasible from both thermodynamic and economic perspectives, industry is still faced with the problem of safely disposing of chemical and mineral wastes in such a manner as to ensure their minimal impact on the environment.

One industry in particular which is being forced to assess the impacts of its wastes on the environment is the minerals processing industry. This industry produces high tonnages of waste streams which include slimes, slags, bag house dusts and leached ores. Slimes consist of solid particles suspended in fluid from the extraction process, while slags, dusts and the leached ores are all granular solid waste particles. All these solid particles contain leachable components in addition to significant quantities of inert material.

These wastes are presently disposed of in various ways. In each case attempts are made to minimise the impact on the environment by containing the waste and any leachate generated within the site of disposal. Slimes are usually disposed of in slimes dams or tailings impoundments. These structures are designed to allow the process fluid to drain from the solid particles and to be returned to the process. The solid particles accumulate in the dams or tailings impoundments until the useful capacity of these structures have been exhausted. Once this stage has been reached, the remaining process fluid is allowed to drain and the dams and tailings impoundments resemble deposits of very fine granular material on closure. There is a possibility for leachate to be generated even after closure when rain water periodically percolates through the system. For this reason these structures not only need to be maintained during their useful lifespan but also for extended periods of time after their closure.

Granular solid wastes in tum are usually disposed of in dedicated waste deposits. These deposits are engineered entities which may or may not have clay or polymer liners to prevent any leachate which may be generated from penetrating the environment. In granular deposits leachate may be generated from rain or ground water which penetrates and percolates through the system. In cases where significant leachate is generated, leachate collection sumps and treatment processes are provided. As in the case with slimes dams and tailings impoundments, these deposits need to be maintained well after they have been filled to capacity with waste. Both slimes dams and dedicated deposits have hazards associated with them. The most obvious hazard is their potential to pollute the environment if they are not sufficiently maintained, especially for the extended periods of time after they have been filled with waste. Further, the liners used in these systems are not perfect and may deteriorate with time, allowing potentially harmful leachate to enter the environment.

A more attractive option which eliminates the need for liners, leachate collection sumps

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and treatment systems is where the waste is physically or chemically pretreated in such a manner to either totally eliminate leachate generation, or to reduce it to release rates which the natural environment can assimilate. Although deposits containing stabilised wastes have the advantages of not requiring maintenance and eliminate the possibility of liner failure, their long term stability needs to be assessed. In this respect, the stability of deposits over at least a few decades needs to determined as well as the stability of deposits over much greater time periods. These time periods are consistent with the time scales being considered in Life Cycle Assessment of waste disposal strategies [Clift 1995].

Since leachate generation and subsequent transport through granular waste deposits represents a significant environmental hazard, an ability to predict these phenomena would be most useful. In the case of slimes dams and dedicated waste deposits, such an ability would enable process engineers to calculate the leachate which would require treating and which would penetrate the environment in the case of a liner failure. This information could then be used to assess the potential environmental hazards of such waste disposal strategies and would form part of a rigorous risk assessment of landfill practice. Since upstream processes directly affect the properties of the waste which needs to be disposed of, an ability to predict the leachate generation as a function of the waste properties would enable process engineers to investigate upstream processing strategies which would produce· wastes which limit the production of leachate. This would enable the processing system to be optimised to limit the impact of its waste on the environment. Further, an ability to predict the leachate generation from deposits which contain stabilised wastes could be used to determine the effectiveness of the stabilisation procedures. In summary, an ability to predict leachate generation and subsequent transport through granular waste deposits would start to provide the minerals processing industry with the tools which it requires in order to determine the most appropriate disposal strategy for its wastes.

In order to predict leachate generation and transport through granular waste deposits, the major physical and chemical processes involved need to be identified. In this work it has been assumed that the leachate is generated by the reaction of a fluid reagent with the granular solid waste particles. These particles usually contain several potentially hazardous and leachable constituents in addition to other components which exhibit buffering capacity within an inert matrix. Here buffering capacity refers to any component which will provide a neutralising capacity to acid which flows through the system. As an example, many wastes contain an alkali silicate matrix which behaves as a buffering component. t::>article characteristics which affect the release of hazardous constituents include particle size, shape and hazardous constituent location. Because of the nature of waste streams, these characteristics vary significantly both between the types of wastes as well as between individual waste particles.

Fluid reagent flow characteristics also play an important role in both the release and subsequent transport of hazardous constituents. The flow patterns are important because they determine the extent to which the fluid is in contact with the individual waste particles. In this work it has been assumed that once hazardous constituents have been released they are transported by the bulk convection of the fluid reagent. Thus the fluid flow patterns significantly affect the mobility of the hazardous constituents. Other physical processes which affect this mobility include adsorption and desorption reactions of the released hazardous constituents onto the surfaces of the solid waste particles.

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Closely associated with fluid flow characteristics is the degree of saturation within the deposit. This is an important consideration because it determines the amount of fluid reagent available for reaction as well as the available wetted surface area of the particles. The influence of the degree of fluid saturation is particularly important in the analysis of South African waste deposits which are rarely saturated with fluid. This is in stark contrast to most North American and European deposits which are usually saturated.

The work presented in this thesis is a start towards determining suitable strategies for the prediction of leachate generation and its subsequent transport through waste deposits which contain granular wastes typical of those produced by the minerals processing industry.

1.1 Statement of the Objectives.

The objectives of the thesis can be summarised as follows:

To derive physical models which describe the generation and subsequent transportation of leachate within waste bodies which contain solid granular material with several leachable constituents.

To represent these models mathematically and to propose . suitable strategies for their solution.

To code these models into suitable computer routines using the appropriate solution strategies.

To identify suitable experimental techniques to quantify any model parameters which are required.

J'o explore methods to verify the models against experimental data which is typically in the form of laboratory column experiments.

1.2 Research Methodolo107.

The literature has been reviewed critically to determine the state of the art with respect to leachate generation and mobility within granular waste deposits. As will be shown in the literature review, none of the existing modelling strategies include a sufficient level of complexity required to either predict the leachate generation or to yield sufficient information about the system which could be used to engineer improved disposal practices. Noting similarities between the leaching of hazardous constituents from waste particles and precious metal heap leaching operations, the modelling strategies used for precious metal heap leaching have also been investigated. As will be shown in the literature review, these too do not contain sufficient detail to adequately model leachate

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generation when dealing with waste particles as opposed to mineral ores. Despite this, it seemed feasible that these modelling strategies could be extended to include the required complexities and this forms the major part of this work.

A second area of existing modelling strategies which has value in attempting to address the complexities associated with leachate generation and mobility in waste bodies is the design of trickle bed reactors. These models too have been reviewed and included in the present development.

The research methodology adopted in this work was to identify or develop models which are sufficiently detailed to predict leachate generation and mobility within granular waste deposits and yet not too complex to preclude implementation. Factors which often limit the usefulness of models include large computational loads, a large number of parameters which need to be determined or when required inputs to the model cannot be determined experimentally. An example of a model input which would be difficult to determine experimentally would be if the model required a full speciation of the components within the waste particles.

The first model investigated was a macroscopic model in which the effects of chemical kinetics, fluid flow characteristics, wetting efficiency and fluid saturation were 'lumped' together into a single parameter. The macroscopic, lumped parameter model describes the leachate concentrations within a granular waste deposit as well as the leachate concentration emanating from the base of a deposit as a function of time. The main reason for investigating this model was its inherent simplicity and its ability to characterise granular deposits as reacting entities. The main disadvantages of this model stem from the lumped parameter used in the model. Because this parameter lumps together the effects of chemical kinetics, fluid flow characteristics, wetting efficiency and fluid saturation on the release of hazardous constituents, it is not possible to isolate the individual contributions of any of these factors. This limits the use of this model for waste deposit design because the main characteristics of a deposit which can be altered include the chemical kinetics and hydrodynamic aspects. Without a knowledge· of which particular aspect is dominant in causing contaminant release it is impossible to engineer better deposits-- other than on a trial and error basis. The lumped parameter is specific to a particular situation and must be determined from an appropriate laboratory column experiment. This .is a severe limitation in that a column experiment, usually referred to as a lysimeter experiment, is required for each different waste and fluid flow scenario envisaged. The disadvantages of lysimeter experiments are the costs involved with such experiments and the long duration of the experiments which typically last for at least a few months and can continue up to two or three years. Because of these limitations it was decided to investigate a model which would be capable of isolating the chemical and hydrodynamic effects on the release of hazardous constituents and which, if possible, obviated the need for lysimeter experiments to determine the model parameters.

This leads to the second model investigated. This model, termed the heterogenous columnar model, also describes the leachate concentrations within a waste deposit as well as the concentration of the leachate emanating from the base of the deposit as a function of time. The main difference is that this model is neither a macroscopic nor a lumped parameter model. Instead, this model calculates the leachate generated as a function of

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the individual particles present in the waste deposit as well as the fluid flow characteristics, wetting efficiency and fluid saturation. The other main advantage of this model is that the required model parameters can be determined from appropriate CSTR type experiments on small samples of the waste material. The time savings incurred by using CSTR type experiments over lysimeter experiments are significant.

The limitations of the heterogenous columnar model as it is presented in this thesis include the fact that only perfect plug flow of fluid through the deposit has been considered, interphase mass transfer limitations or resistances between the bulk fluid reagent and particle surfaces have been neglected, and, adsorption and desorption of released hazardous components has not been considered. It is important to note that more complex flow scenarios, interphase mass transfer and adsorption and desorption reactions can be included into the present model. The model has been specifically coded in a modular manner to allow the incorporation of these aspects.

1.3 Thesis Layout.

The thesis commences with a review of relevant considerations when modelling leachate generation and mobility in granular waste deposits. In this section, more detailed information on particulate and hydrodynamic characteristics of the waste and waste deposit is presented. This is followed by a critical review of modelling strategies with respect to the release of hazardous constituents from granular waste deposits. This review covers existing leachate generation modelling strategies, heap leaching modelling strategies and trickle bed reactor design strategies.

Chapter 3 presents the model development for the macroscopic, lumped parameter model. This chapter includes the derivation of the equations required for this model, an investigation into an appropriate solution strategy and details with respect to computer routines which have been written to implement the solution strategy. Also included in this chapter are details of how to fit the model to lysimeter data. The limitations of the macroscopic, lumped parameter model indicated that a more complete, particle scale model would be required to determine sufficient detail about the system in order to facilitate active engineering of the deposit to limit the release of hazardous constituents from granular waste deposits.

The more complete model, which determines the release of hazardous constituents from individual waste particles and relates this information to the overall waste deposit performance, is developed in Chapters 4 to 6. Chapter 4 is a summary of Dixon's [1992] chemical reaction model which describes the progression of reactions within an individual waste particle. As will be shown, this model has limited applicability on its own. Waste deposits consist of a size distribution of particles and a finite amount of fluid reagent. The performance of this system, rather than that of a single particle, is the desired end product. For this reason the chemical reaction model of Dixon [1992] was extended to form a suitable CSTR model in Chapter 5 and a heterogenous columnar type model in Chapter 6. A CSTR type model has been included due to the fact that the model

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parameters required in the heterogenous columnar model can be determined from a CSTR type experiment. The heterogenous, columnar model has been verified against experimental data presented in a paper by Roman et al. [ 197 4]. The details of this verification have also been included in Chapter 6.

The final chapter presents a summary of the conclusions and recommendations which can be made from this work .

...

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Chapter 2. Relevant Considerations when Modelling Leachate Generation and Mobility.

This chapter discusses important aspects of leachate generation and mobility within granular waste deposits. As discussed briefly in the introduction, both the physical composition of the waste particles and the fluid flow characteristics within the waste deposit affect the manner in which hazardous constituents are released from the waste. The first section of this chapter considers these particulate and hydrodynamic considerations which are important in modelling leachate generation. In this section, information from the literature on trickle bed reactor design has been used to help understand the complex flow patterns of fluid within granular waste deposits.

The existing leachate generation and mobility models which can be found in the literature have been reviewed. This section critically assesses which of these models have any potential to predict leachate generation within deposits which contain granular wastes typical of those produced by the minerals processing industry.

As alluded to in the introduction, heap leaching processes, designed to extract precious· metals from ores, share similarities to leachate generation within waste deposits. In both cases the leachate is generated from the reaction of a fluid reagent with solid particles. Both processes have a similar dependence on the solid reactant location within the ore or waste particles and the fluid flow characteristics. The major difference between the two processes is that the generation of leachate is desired in the case of heap leaching and undesired in the leaching of hazardous constituents. This leads to significant differences between the systems. The fluid reagent used in heap leaching for example is usually chosen in such a manner as to selectively extract one desired component from the ore matrix. This is in contrast to the leaching of hazardous constituents where several contaminants are leached simultaneously by fluid percolating through ·the deposit. Further, heap leaching processes are designed to optimise the wetted area of the particles. When waste deposits are designed, if any consideration is given to particle wetting, it would be to limit the surface area of the particles in contact with the fluid percolating through the deposit. Despite these differences between the two systems, the models for heap leaching of precious metals are a good starting point for developing suitable models to predict leachate generation within waste deposits. For this reason the general strategy behind these models is presented.

The final section of this chapter deals with modelling leachate generation and mobility within unsaturated deposits.

2.1 Particulate and Hydrodynamic Considerations.

2.1.1 Particulate Considerations.

Granular solid wastes produced by the minerals processing industry vary considerably from one waste stream to the next in terms of the number and type of reactive

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components present within the particles. Even within a single waste stream, the spatial distribution of the components may vary between the different sized particles. These differences need to be investigated to determine their significance in the modelling of leachate generation.

Number and t,me of reactive components present within the waste particles.

The most desirable form of waste is a waste in which the constituent particles are totally inert to fluid reagent percolating through the deposit. In this case there would be no reactive components and leachate could not be generated. Although wastes of this nature are the goal of pretreatment and stabilisation processes, they are seldom achieved in reality. The simplest waste type which is capable of producing leachate is the waste which contains a single reactive component. Such wastes are very uncommon. Far more probable however are wastes which contain two or more reactive components which display significant leaching potential.

The reactive components in waste particles can either be hazardous constituents or other components, termed buffering components, which merely consume fluid reagent but do not release any hazardous constituents. Typical hazardous constituents in minerals processing wastes are heavy metals while the buffering capacity is usually due to fluxing agents.

It is difficult to provide a general description of the relative amounts of leachable hazardous constituents, buffering and inert material within waste particles. Leached ores or tailings residues, for example, contain a relatively high fraction of inert material with trace amounts of leachable hazardous constituents and buffering material. This is in contrast to a slag waste stream which has a high buffering material content in addition to leachable hazardous constituents and inert material.

Although there may be several potentially leachable hazardous constituents within waste particles, usually only a few occur in sufficient quantities or are sufficiently reactive to be of concern. -For example, although wastes from the minerals processing industry often contain several heavy metals, usually only one or two of these are in significant concentrations to pose a hazard if leached out of the waste.

Hazardous Constituent location within waste particles.

Hazardous constituents present in waste particles may either be distributed homogenously throughout the particle or be concentrated onto its external surface. These differences in hazardous constituent location are both waste specific and particle ·size specific and are usually a result of the conditions under which the waste was produced. As an example of hazardous constituent location as a function of waste type, compare the hazardous constituent location in a slag waste stream and an electric arc furnace dust. The hazardous constituents present in a slag waste stream would be expected to be distributed reasonably homogenously throughout the particle. This differs

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markedly from an electric arc furnace dust which usually exhibits surface concentrations of heavy metals much higher than the bulk concentrations within the particles [Driesinger et al. 1990].

Turning to the case of hazardous constituent location as a function of particle size, work conducted at the University of Cape Town on specific ferro-alloy waste products indicated that different sized particles exhibit different surface hazardous constituent concentrations [von Blottnitz 1994].

2.1.2 Hydrodynamic Considerations.

Hydrodynamic aspects are concerned with the transport of fluid through waste deposits and the manner in which the fluid and solid waste are contacted. Hydrodynamic aspects, for granular waste deposits as well as for solidified monolithic structures, have been investigated in order to determine their significance on the modelling of leachate generation. Monolithic structures are obtained when granular wastes are mixed with suitable binding agents, cement being one example, in order to physically bind the particles together. Even although the particles are physically bound together, monolithic structure exhibit a continuous pore structure through which fluid can enter the structure. Although monolithic structures are not directly within the brief of this work, the fluid flow patterns associated with these structures can be considered as a limiting case for granular waste deposits which contain very fine, densely packed material.

Fluid flow patterns within granular waste deposits.

Fluid flow patterns through granular waste deposits range from near perfect plug flow to highly irregular flow patterns involving a few preferential flow paths for the fluid reagent. Knowledge of the flow patterns is important because it is related directly to the solid-liquid contacting efficiency.

Trickle bed reactors, common within the process engineering community, are packed bed reactors through which one or more fluid is allowed to flow. These reactors exhibit a _ wide variety of fluid flow regimes which range from strictly trickle flow, in which a single liquid flows downward through the reactor under the influence of gravity, to pulse and foaming flow, caused by high flowrates of gases and liquids through these reactors. Since the physical situation in a trickle bed reactor operating in trickling flow regime is comparable to fluid percolation through granular waste deposits, a knowledge of the flow patterns in these reactors can be used to understand the fluid flow patterns in granular waste deposits.

A review of the literature on trickle bed reactors shows that, traditionally, with respect to hydrodynamic considerations, only two quantities, the liquid holdup ·and wetting efficiency, have been measured and correlated [Columbo et al. 1976; Schwartz et al. 1976; Mills and Dudukovic 1981; Ramachandran et al. 1986; Gianetto and Specchia 1992]. Although these two quantities are useful to describe the overall bulk effects of the

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hydrodynamic interactions, they offer little insight into the flow patterns.

Until fairly recently, relatively little was understood about the flow patterns in trickling flow trickle bed reactors due to the difficulties involved with determining these patterns. A novel use for computer assisted tomography (CAT scans) has eliminated most of these difficulties and enabled Lutran et al. [1991] to investigate the flow patterns in a packed bed of equi-sized glass spheres. At the particle level, they identified two distinct types of fluid flow which they termed 'film' and 'rivulet' flows.· Film flow represents the case where the fluid tends to cover most of the particle surface area, while rivulet flow describes the case where the flow of fluid over a particle is restricted to a narrow band. They also identified pendular structures and liquid pockets at the · microscopic level. Pendular structures reside at the contact points between spheres while liquid pockets fill the pore space between spheres. At the macroscopic level Lutran et al. [1991] identified fluid filaments. A filament was defined to be a stream of fluid flowing down the packed bed. In effect, a filament could be considered as a string of connected liquid pockets. These definitions are graphically depicted in Figure 2-1 (taken from Lutran et al. [1991]).

Figure 2-1. Film, rivulet and filament flow patterns as described by Lutran et al. [1991].

Rivulet

Pendulu StructW'H

Lutran et al. [1991] investigated <the effect of liquid flow rate, the influence of surface conditioning, the influence of particle size, the influence of inlet configurations and the effect of flow history on the flow patterns. A typical result from their work is shown in Figure 2-2 (taken from Lutran et al. [1991]). CAT scans (a) through (t) represent successive vertical planes from the front to the back of a square column packed with equi-sized glass spheres. Filament flow can clearly be seen in these figures as the darker regions moving from the top to the bottom of the column. The experimental conditions under which these CAT scans were taken can be summarised as follows: 3mm glass spheres were used, distilled water was evenly supplied through a uniform inlet distributor

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at a rate of 3.1631/m2 s and the particles were initially dry.

Figure 2-2. CAT scans used to investigate the flow patterns in a square column packed with equi-sized glass spheres. (Taken from Lutran et al. [1991].)

a b c

·'··1· ~-!~~~ ., . . ·.

:~~~~; -:.:.

Although Lutran et al. [1991] do not discuss correlating their findings, it is very unlikely that any correlation would employ the particle Reynolds number as a parameter. The main reason for this is due to the fact that pore size and differences in local porosity seem to play an important role in the flow patterns which are established. As an example, Lutran et al. [1991] have shown that for a constant flowrate, film flow is more prevalent in packed beds containing larger particles (6mm spheres) compared to packed beds containing small particles (3mm spheres) in which filament flow is observed. They attribute this to the fact that packed beds which contain larger particles will have larger

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pores between the particles. They suggest that at the fluid flow rate investigated (3.1631/m2 s), there was insufficient fluid to fill any of the pores between the 6mm spheres and thus establish filament flow. As the fluid flowrate was increased, more filaments were established which supports this hypothesis.

By a similar argument, any regions which exhibit a local decrease in porosity would favour the formation of filaments. Filament formation would also be aided in these areas by the increased number of solid-solid contact points which allows fluid to more easily distribute to these areas due to the lower surface tension forces on the fluid surface [Zimmerman and Ng 1986]. Wastes which contain a size distribution of particles or non-uniformly shaped particles usually exhibit localised regions of decreased porosity. This implies that these deposits would favour filament flow. It is important to note that channelling of fluid, where the fluid flows through deposits in preferential flow paths, is also probably a result of regions of decreased porosity. Channelling results in fluid short circuiting sections of the deposits. Although this is a highly irregular flow pattern which is extremely difficult to model, it is a very desirable flow pattern for fluid in waste deposits because it reduces the number of particles with which the fluid comes into contact as it percolates through . the system.

Fluid redistribution on the other hand is accomplished by capillary and viscous forces. Capillary forces are inversely proportional to the pore size [Ng and Chu 1987]. Thus the capillary pressure is higher in deposits which contain small particles because the pores are relatively small in these deposits. Capillary forces also result in higher void space liquid holdup [Ng and Chu 1987]. This implies that deposits containing smaller particles will contain proportionately more fluid in their pore spaces compared to deposits containing larger particles.

Using the information discussed above, the following heuristics of fluid flow patterns in granular waste deposits are suggested. These are intended to give an idea of the most likely fluid flow patterns under different conditions.

The most likely fluid flow patterns in deposits which contain relatively large particles, such as leached ore particles, would be that of film flow. In this case the fluid would most likely tend 'to cover the surfaces of the particles as it progressed from one particle to the next. As the standard deviation for the size distribution of the particles increases, so too will the likelihood for filament formation and eventual channelling increase. Deposits of this nature are also most likely to exhibit a very low degree of fluid saturation. This implies that the external fluid holdup, that is the holdup of fluid in the pore spaces, would be very low.

As the average particle size decreases, the degree of saturation will increase due to capillary effects. Likely flow patterns include film flow with associated filament flows.

In the case where the deposit contains very fine particles, such as are encountered in slimes dam and tailings impoundment residues, the most likely flow patterns would be filament flow, and the deposit would most probably be almost totally saturated. The size distribution . of particles is unlikely to affect the flow characteristics due to the high capillary forces which would be present. In all probability, the flow patterns in such

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deposits could be described by plug flow models.

Fluid flow patterns within _solidified structures.

Cote and Birdle [1987] have discussed the likely flow scenarios which can be associated with solidified monolithic structUres. In summary they considered the situation shown in Figure 2-3 where the monolithic structure is surrounded by materials of different permeabilities.

Figure 2-3. Layout of a waste form in a landfill. (Taken from Cote and Birdle [1987].)

Ground surface

Material 3

Material 2

Material I

The first case they investigated is when the monolithic structure is in contact with a finite volume of static groundwater. This corresponds to the case when the hydraulic conductivity of the materials (1) and (2) are much smaller than the monolithic structure or material (3). Physically this situation represents the case where a pool of water exists on top of the waste deposit. In this situation, the water penetrates the solidified structure by diffusion.

The second situation addressed was when groundwater flows around the monolithic structure. This is the most common scenario because monolithic structures typically have -hydraulic conductivities which are several orders of magnitude lower than that of the surrounding ground. Because groundwater will follow the path of least resistance, very little, if any, will flow through the structure. Even although there may be no convective flux through the structure, there is still the possibility of a lateral diffusive flux into the structure.

The last case considered is when the groundwater flows through the monolithic structure. This typically occurs when the monolithic structure fails and the hydraulic conductivity increases to a point that it is comparable to that of the surrounding materials. In many respects this situation can be compared to a granular deposit where the fragments of the original structure represent the 'particles' in the deposit.

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2.2 Review of Existin2 Leachate Generation and Mobility Models.

Literature models which address leachate· generation and mobility can be divided into four classes. The first two classes deal with predicting the breakthrough curves from granular waste deposits. The breakthrough curves are the curves which are formed by plotting the dissolved hazardous constituent concentrations which emanate from the base of the deposit as a function of time. The third class applies to modelling hazardous constituent release from solidified monolithic structures. The last group is concerned with hazardous constituent migration away from waste deposits.

All of the literature models are summarised in Table 2-1 which highlights their respective areas of application, advantages and disadvantages.

2.2.1 Empirical Models. -

Purely empirical models fit experimental results obtained from lysimeter studies to an exponentially decaying function of time. These models [Demetracopoulos et al. 1986] were the only models up until the mid 1980's to describe hazardous constituent release from waste deposits. The mathematical form of the model can be summarised as:

where C0

t

C = C e <-Pt> 0 (2-1)

hazardous constituent concentration in the leachate at the time of initial breakthrough (t=O),

time, and,

an empirical constant.

Work carried out at the University of Cape Town [Petersen 1994] has shown that the fitting of lysimeter data to such a function often leads to a poor correlation. Even if the correlation was excellent, such a model could not be used to scale up to full scale deposit proportions because no size dimensions appear in the model. Thus in order to determine the breakthrough curve for leachate from granular deposits, where the fluid flow can often be approximated by one . dimensional flow, a lysimeter of identical height to the envisaged deposit would be required. The only use of such a model would be the extrapolation of data to predict the release of hazardous constituents in the future. Because of the poor correlation and limited predictive ability of this model it is concluded that is has little applicability to modelling the release of hazardous constituents from hazardous waste. deposits.

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n .....

. V

I

Tab

le 1

. S

umm

ary

of

Mod

els

whi

ch D

escr

ibe

Con

tam

inan

t R

elea

se

from

Haz

ardo

us

Was

te D

epos

its.

Mod

el:

Not

es:

App

lica

tion

:

Lu

et a

l. (1

981)

. F

irst

mod

el t

o de

scri

be

Non

e.

brea

kthr

ough

cu

rve.

Dem

etra

copo

ufos

(1

986)

. C

onta

min

ant

rele

ase

base

d o

n t

he

Dir

ect

extr

apol

atio

n an

d in

itia

l co

ntin

uity

equ

atio

n ap

plie

d to

a

anal

ysis

of

lysi

met

er d

ata.

ly

sim

eter

as

a si

ngle

ent

ity.

Bat

chel

or

(199

0).

Mod

el b

ased

on

sem

i-in

fini

te-m

edia

M

odel

ling

con

tam

inan

t re

leas

e fr

om

diff

usio

n th

eory

. so

lidi

fied

str

uctu

res.

C

heng

and

Bis

hop

(199

0).

Row

e an

d B

ooke

r M

odel

s de

scri

be c

onta

min

ant

Det

erm

inat

ion

of

over

all

I 199

0,19

85a,

1985

bl.

mig

rati

on a

way

fro

ni h

azar

dous

en

viro

nmen

tal

impa

ct o

f ha

zard

ous

was

te d

epos

its.

w

aste

dep

osit

s.

Dan

ce a

nd R

eard

on

( 198

3 (.

Mas

lia

et a

l. (1

9921

.

Sud

icky

et

al.

(198

31 .

Vog

t (1

991)

.

Bru

nn

.. , a

l. [ 1

9741

. M

odel

ling

con

tam

inan

t re

leas

e fr

om

gran

ular

haz

ardo

us w

aste

dep

osit

s.

Rom

an

(197

41.

Sha

fer

(197

9).

Dix

on (

1992

).

Con

tam

inan

t re

leas

e ba

sed

on t

he

Mod

elli

ng c

onta

min

ant

rele

ase

from

co

ntin

uity

equ

atio

n ap

plie

d to

the

gr

anul

ar h

azar

dous

was

te d

epos

its.

in

divi

dual

par

ticl

es i

n th

e de

posi

t.

Mod

elli

ng c

onta

min

ant

rele

ase

from

m

onol

ithi

c ha

zard

ous

was

te

depo

sits

.

Adv

anta

ges:

D

isad

vant

ages

:

Rel

ativ

ely

sim

ple

to u

se.

Lum

ped

para

met

er

anal

ysis

.

Uni

quel

y ch

arac

teri

ses

the

depo

sit

as

Lim

ited

abi

lity

to

pred

ict

perf

orm

ance

a

reac

ting

ent

ity.

un

der

diff

eren

t hy

drod

ynam

ic

cond

itio

ns.

Rel

ativ

ely

sim

ple

to u

se.

Lim

ited

abi

lity

to

pred

ict

perf

orm

ance

un

der

diff

eren

t co

ntam

inan

t an

d bu

ffer

co

ncen

trat

ions

.

.

The

se m

odel

s be

gin

to a

ddre

ss t

he

Ass

umes

tha

t di

ffus

ion

of

the

flui

d in

to

unde

rlyi

ng r

elea

se

mec

hani

sms.

th

e in

divi

dual

par

ticl

es i

s th

e ra

te

lim

itin

g st

ep.

Onl

y co

nsid

ers

a si

ngle

·che

mic

al

reac

tion

tak

ing

plac

e.

Onl

y ap

ply

to s

itua

tion

s in

whi

ch a

ll o

f th

e pa

rtic

les

arc

wet

ted

and

in w

hich

no

pre

forc

ntin

l fl

ow p

aths

, st

agna

nt

zone

s o

r dr

y sp

ots

occu

r.

The

y al

so d

o no

t ad

dres

s cy

clic

wet

ting

and

dry

ing

cycl

es.

Doe

s no

t as

sum

e th

at

diff

usio

n is

the

O

nly

appl

y to

sit

uati

ons

in w

hich

all

of

rate

con

trol

ling

mec

hani

sm.

the

part

icle

s ar

c w

ette

d an

d in

whi

ch

no p

refe

rent

ial

flow

pat

hs,

stag

nant

In

clud

es t

he p

ossi

bili

ty o

f m

ore

than

zo

nes

or

dry

spot

s oc

cur.

T

I1ey

als

o d

o

one

chem

ical

rea

ctio

n ta

king

pla

ce.

not

addr

ess

cycl

ic w

etti

ng a

nd d

ryin

g cy

cles

.

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2.2.2 Models which make use of the Continuity Eguation.

The second group of models makes use of the fluid continuity equation to describe the contaminant migration through the system. Demetracopoulos et al. [1986] have used such an approach to model leachate generation from domestic waste landfills. They considered the refuse material as a homogenous, partially saturated porous medium. Although domestic waste landfills often contain laminates, which preclude any attempts to approximate the fluid flow as one dimensional, Demetracopoulos et al. [1986] limited their study to cases in which the fluid flow can be approximated as one dimensional. Because of these assumptions, the refuse and flow characteristics are comparable to those found in granular waste deposits.

Demetracopoulos et al. [1986] make use of a hydraulic flow equation to predict the flow of fluid through the system. Demetracopoulos et al [1984] describe the derivation of this equation which was then solved numerically by Korfiatis et al [1984]. These equations can be summarised as:

where e

K(O) q D(O) t z

where I/;

ae + aK(8) _ _E_ [D (S) ae 1 =o at az az az (2-2)

q=K(8) -D(8) ~~ ( 2-3)

moisture content, or the fraction of the control volume occupied by liquid (m3/m3); hydraulic conductivity of the medium, (m/s); volumetric flux per unit bulk area (superficial velocity), (m/s); yapillary diffusivity coefficient, defined by equation (2-4) below, (m2/s); time, (s); and; space coordinate, measured vertically downward (m).

D(8) =-K(8) ~ d8

(2-4)

tension suction head which is defined as the negative capillary pressure potential [Shaw 1994].

The tension suction head versus moisture content relationship which was used can be summarised as:

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where s b

indicates saturation conditions; and; fitted empirical constant.

(2-5)

The release of hazardous waste constituents from a granular waste deposit was modelled using a continuity equation. The resulting equation can be summarised as:

where C E(O) q R

a (6c) + a ( qc) =__£_ rn E(S) ac1 +e R at az az az (2-6)

fluid phase concentration of the hazardous constituents (kg/m3);

longitudinal dispersion coefficient (m2/s); volumetric flux per unit bulk area (superficial velocity) (m/s); and; source or sink term (kg/m3s).

By assuming that the source or sink term R, which corresponds to the rate of release of hazardous constituents, is controlled by the mass transfer between the solid and liquid phases, an equation which describes the generation and transport of non-biodegradable hazardous constituents was obtained and can be summarised as:

where k' s

a(ec) + a(qc> =__£_ [e E(6) ac1 +e k'_§_ (c -c) at az az az S0

st ( 2-7)

rate coefficient for mass transfer (l/s); local solid mass fraction of hazardous constituent available for transfer (kg/m3

);

local solid mass fraction of hazardous constituent available for transfer at time t=O (kg/m3

); and; maximum possible hazardous constituent concentration in the fluid phase (kg/m3

).

Models of this nature are not limited to the case where mass transfer effects control the rate of release of hazardous constituents. By using appropriate expressions for the source or sink term, R, the model can be adapted to describe the situation where chemical kinetic or intra-particle diffusion resistances are rate limiting. In each case, a parameter is being used to quantify the rate limiting mechanism in the release of hazardous constituents.

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Demetracopoulos et al. [ 1986] extended the model to incorporate biological activity. This resulted in two coupled partial differential equations, one which describes the growth and transport of the microorganism population and one which describes the release and transport of hazardous constituents.

The merit of such a model is that it offers a relatively simple method by which to study the release of hazardous constituents from waste deposits.

The disadvantage of this model is that there is no way of predicting the parameters used to describe the rates of release of hazardous constituents. These parameters need to be determined from appropriate lysimeter experiments.

2.2.3 Models Suitable for Predictin2 Leachate Generation from Solidified Monolithic Structures.

Batchelor [1990],Bishop [1990] and Cheng and Bishop [1990] all have developed models which are suitable to predict leachate generation from solidified monolithic structures. From CSTR leach tests on fragments of solidified structures, these investigators found the release of hazardous constituents to be dominated by diffusion internal to the solidified structure. The model considers the monolith as a single entity and determines the rate of release of hazardous constituents using semi-infinite.:.media diffusion theory. The following form of equation is almost always used in this approach: ,

where

(2-8)

hazardous constituent loss during leaching period n (kg); initial amount of the hazardous constituent present in the specimen (kg); volume of the specimen (m3

);

surface area of the specimen (m2);

cumulative time to the end of leaching period n (s); and; effective diffusivity (m2/s).

Equation (2-8) is based on the following semi-infinite-media equation:

where c x

C(X, t) =C0

erf( X ) 2./ (D9 t)

(2-9)

hazardous constituent concentration at position X, distance from the outer surface of the monolith, and,

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t time.

A limitation with respect to the use of equation (2-9) which is not mentioned by any of the investigators is that the following condition must hold before this equation can be applied to finite systems [Welty, Wicks and Wilson, 1984]:

v 2S./Det

> 2 (2-10)

One reason for this omission may be because the assumption of a constant mid-plane hazardous constituent concentration can be considered to be a worst case scenario. This implies that the models would tend to predict a greater loss of hazardous constituents than would occur in finite systems. Another reason for this omission could be because the authors did not consider evaluating their models at times sufficiently large to violate this condition. ·

In general, the leach type models are suitable to extrapolate data in time as well as to predict the release of hazardous constituents from various sized monolithic structures.

The limitation of these models is that they cannot be used to extrapolate the results to different hazardous constituent and buffer concentrations within the solidified matrix. The reason for this is that the effective diffusivity is a fitted parameter which is affected by the concentrations of the hazardous constituents, buffer and inert species within the solidified waste [Cheng and Bishop 1990].

Cote and Birdle [1987] have made use of this class of models to investigate several long term leaching scenarios for solidified waste forms. In particular they investigated the effects on the release and mobilisation of hazardous constituents of the hydraulic regime of the groundwater, chemical characteristics of the groundwater, hydraulic conductivity of the solidified structure and chemical speciation of the hazardous constituents within _ the waste matrix. Figure 2-4 is a summary of the results of their work. This figure can be used to estimate the release rates of hazardous constituents from monolithic structures. As an example, consider the release of hazardous constituents from a fractured monolithic structure. Such a situation would resemble a granular waste deposit and fluid would most likely percolate through the fractured structured as discussed in section 2.1.2. Typical release rates of soluble hazardous constituents in such a situation are shown in region (F) in Figure 2-4. This region indicates that very high leaching rates would be observed ( = 10 000 mmol m-2 day-1

) and that the leaching processes would cease within the first few months due to depletion of the hazardous constituents. Insoluble hazardous constituents could be released by active leaching and typical release rates are shown by region (H) in Figure 2-4. Notice that the leaching rates for insoluble constituents ( =1 mmol m-2 day-1) is much lower than for soluble components as expected.

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Figure 2-4.

I ... 0

"' .. I e 0 e e

• 0 -"' -= .s:; u 0

• ~

Inference of leaching rates following different leaching scenarios. (Taken from Cote and Birdle [1987].)

waste Form Static Aow.ng Grounawatet 10 000

Cattamnant Parn.&tllllty Groiniwatet around the waare t~!llewure

IOw pH neutral pH low pH neutral pH

aoUlle IOw

D I I E B ~ hlgll

1000 inaol&'* low G G il ir180iutll8 hlgll tj

100

10

1.0

0.01 @ "" 'I\ -=- =- ·- :. ... ~

--- Calculated rote

Anticipated trend

0.001

o.0001-l------1''-------r-~-----------r-------------r------------_,_----~------

0.01 0.1 1.0 10.0 I 00.0

Time (years)

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2.2.4 Models Describin2 Contaminant Migration away from Deposits.

The last group of models includes work on contaminant migration away from hazardous waste deposits. These models uncouple the hydrodynamic analysis from the chemical reaction aspects, assuming . that no interaction occurs. The hydrodynamic part, which is a groundwater flow problem, is modelled using a Darcy law approach which incorporates a bulk hydraulic conductivity. A bulk hydraulic conductivity is an average measure of the distance which fluid would move through a porous medium per unit time. This quantity is a function of both the fluid type and fluid saturation within the porous medium [Shaw 1994]. Saturated hydraulic conductivities are usually determined experimentally. Hydraulic conductivities under unsaturated conditions can also be determined experimentally but are much more difficult to determine than saturated hydraulic conductivities [Fourie 1995]. An alternative approach to determine unsaturated hydraulic conductivities is to use appropriate models, prese_nted in groundwater flow texts, which use the saturated hydraulic conductivity as a parameter [Freeze and Cherry 1979]. It is important to note that bulk hydraulic conductivities are quantities which are used to describe the macroscopic flow rates of fluids in porous media. As such, no information with respect to localised flows within the medium can be determined. In cases where this level of detail is required or in cases where local variations in hydraulic conductivities preclude the use of a bulk hydraulic conductivity, the full tensorial form of the hydraulic conductivity would need to be evaluated. Knox et al. [1993] present information with respect to the full tensorial definition of hydraulic conductivities.

The chemical reactions are modelled either by adsorption/desorption isotherms, which are based on experimental results [Rowe and Booker 1990, 1985a, 1985b; Dance and Reardon 1983; Maslia et al. 1992; Sudicky et al. 1983] or by totally predictive thermodynamic analyses [Vogt 1991].

One of the assumptions used in these models is the value assigned to the leachate concentration at the base of the deposit. This is estimated by determining the volume of fluid within the granular deposit and assuming that all of the hazardous components are released into this fluid subject to adsorption and desorption equilibria. Once this leachate concentration has been estimated, the subsequent transport of the leachate through the underlying ground is modelled. Since these models do not address leachate generation aspects they could only be used as suitable mobility models within granular waste deposits. If this strategy could be used as a mobility model it would have the advantage of including the effects of adsorption and desorption on leachate mobility.

Before these models could be used to describe leachate mobility in granular waste deposits, the adsorption/desorption isotherms of the hazardous constituents onto the granular particles would need to be determined. The determination of these isotherms for granular waste particles will be significantly more complex than for inert ground samples. This is due to the fact that it is difficult to determine an adsorption/ desorption isotherm for a material which is itself releasing the same components. Methods to deconvolute the effects of leachate generation from adsorption and desorption processes would need to be determined.

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It is unlikely that thermodynamic analyses could assist to predict the chemical reactions taking place because of the complex chemical compositions of waste particles. In most cases it is impossible, due to physical and financial· constraints, to determine the initial hazardous constituent and buffering material speciation required for thermodynamic analyses.

Although this group of models has limited applicability for the objectives as defined, it will be useful when a complete environmental impact assessment of a hazardous waste deposit is required. Once the release of hazardous constituents from a deposit has been calculated, this information can be used as the input data for the migration models. The subsequent migration through the environment, and thus the health risks and environmental impact, could then be determined.

-2.3 Summary of the Strate1:y Adopted in Precious Metal Heap Leachin1:

Models.

The general strategy used [Roman et al. 1974] in the analysis of heap leaching is to divide the heap conceptually into columnar sections. Each column is then considered as a simple one dimensional, non-catalytic reactor. The progression of the reactions in the individual particles is followed using a suitable chemical reaction model. These reaction models require the concentration of the fluid in contact with the particles. Thus by calculating the fluid concentration in contact with the particles and the progression of the reactions as a function of time, the dissolved hazardous component concentration can be determined. These concentrations can then be used to calculate the breakthrough curve. In order to calculate the fluid concentration in contact with the particles, the columnar sections are further divided into a set of discs which are stacked on top of each other as shown in Figure 2-5. The fluid concentration within each disc is assumed to be constant and is calculated by a simple mass balance. This strategy is summarised in Figure 2-6.

Figure 2-5. An ore heap conceptually divided into columnar sections and the columnar sections divided into discs. (Figure taken from Roman et al. [1974].)

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Figure 2-6. Summary of the strategy used to determine the breakthrough curve in heap leaching operations.

Iterate in time.

End.

Iterate in space.

• Calculate the concentration of fluid in contact with the particles within the disc.

• Calculate the progression of the reaction within the particles using a suitable chemical reaction model.

•Update the dissolved product concentration within each disc.

·Calculate the breakthrough curve.

Braun et al [1974], Roman et al. [1974] and Shafer [1979] have used this approach to model heap leaching operations. In all of these cases very simple hydrodynamic behaviour has been considered. This is evident in that all of the particles within each disk were assumed to be totally· wetted. For the application of heap leaching this is not a bad assumption because totally wetted particles is the objective of heap design and lixiviant spray patterns. Although it was not explicitly stated, these investigators have also assumed that no significant preferential flowpaths or stagnant zones are present.

The chemical reaction model almost always used in this approach is a shrinking core model. This implies that diffusion of fluid reagent into the individual particles is the elementary rate controlling step. This can be a severe limitation because in some cases the chemical reactions are sufficiently slow to result in a homogenous reaction. In these cases, the intrinsic kinetics of the chemical reactions become very important. The simple shrinking_ core model as used by Roman et al. [1974] has a further limitation in that it

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only considers a single reaction taking place.

Dixon [1992] has developed a chemical reaction model which eliminates these shortcomings. Dixon's approach is similar to that of Demetracopoulos et al. [1986] in that it makes use of the continuity equation to model chemical release. The main difference is that Dixon applies the analysis to an individual particle while Demetracopoulos applied it to a lysimeter as a single entity.

Dixon's model includes information on the diffusivity of fluid reactant into the particles and the intrinsic kinetics of the multiple reactions which take place. Although the intrinsic kinetics are not explicitly obtained in Dixon's model, the ratio of the diffusivity over the intrinsic kinetics is determined. In many ways this corresponds to determining the effective reaction kinetics, which include the effects of intra-particle diffusion, of the waste particles. The model is developed in such a manner that once the effective reaction kinetics of a particular sized particle have been determined, the technique can be extended to other sized particles. Dixon's model also makes provision for surface solid reactant concentrations which differ from bulk solid concentrations within the particles.

In summary Dixon's chemical reaction model makes provision for the following:

the diffusivity of the fluid reagent into the particles as well as the intrinsic kinetics of the solid reactant within the particles,

multiple competing reactions, and,

surface solid reactant concentrations which differ from the bulk solid concentrations within the particles.

Dixon made use of this model to describe copper release from a heap leaching operation. He made similar assumptions concerning the hydrodynamic interactions to those of Roman et al. [1974]. Not withstanding the complications of preferential flow _ paths, Dixon's model has an excellent capacity to predict the release of hazardous constituents from hazardous waste deposits which contain granular material.

Dixon's model can also be used to model the release of hazardous constituents from a monolithic structure. The ratio of the effective diffusivity of the fluid into the monolith over the rates of the hazardous constituent release can be determined by conducting a CSTR test on small fragments of the monolith. This information can then be used to predict the release of hazardous constituents from the monolithic structure. This is a more sophisticated method to the one adopted by Batchelor [1990], Bishop [1986] and Cheng and Bishop [1990], because it does not assume that diffusion is the controlling resistance or make use of the semi-infinite-media assumption. This method also has a greater predictive power in that it can also be used to investigate the effect of hazardous constituent and buffer concentration on the rate of release of hazardous constituents which the prior methods could not.

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2.4 Modellin& the Release of Hazardous Constituents from Partially Saturated Granular Waste Deposits.

No models exist in the literature which describe the release and subsequent transport of hazardous constituents under unsaturated flow conditions.

Probably the most comprehens_ive attempt to include the effects of unsaturated conditions on leachate generation are those of Demetracopoulos et al. [1986]. They include these effects by using a hydrodynamic equation for unsaturated flow. These equations, described previously in equations (2-2) to (2-5), are often referred to as groundwater flow equations. Hydrodynamic equations or groundwater flow equations yield information about the local levels of saturation as well as local fluid flows. In the equations presented, which are already in one dimensional format, the saturation of fluid and fluid flow within a waste deposit can be determined as a function of position within the waste deposit and time. Although Demetracopoulos et al. [1986] determine the effect of unsaturated conditions on fluid flow, they do not consider the effect of these conditions on the mass transfer of hazardous constituents. Since they made use of mass transfer to describe the rate of release of hazardous constituents in their model, the influence of this factor should have been investigated. To circumvent the problem, Demetracopoulos et al. define a distribution coefficient, which relates the hazardous constituent concentration in the fluid to the hazardous constituent concentration in the waste particles, specific to the situation being investigated. This distribution coefficient needs to be determined experimentally for each situation. In effect, this coefficient includes the average effects of the degree of saturation on hazardous constituent release.

The only other attempts to include the effects of the level of saturation on leachate generation can be found in the heap leaching models which usually include a saturation parameter [Roman et al. 1974]. The saturation parameter represents the average level of saturation within the lysimeter. All of these models further assume that all of the particles within the heap are totally wetted with fluid. Although this assumption is probably valid for heap leaching, it will almost certainly not hold in unsaturated waste deposits. The reason for this is that fluid which percolates through unsaturated waste deposits usually does so in a fairly random manner.

The level of particle wetting is important in the effective operation of trickle bed reactors and several researchers have investigated means to determine a suitable wetting factor [Columbo et al. 1976; Schwartz et al. 1976; Sicardi et al. 1980; Mills and Dudukovic 1981; Ramachandran 1986]. A wetting factor is a simple factor which describes the average fraction of the particle surface area covered by fluid. It is felt that the inclusion of similar wetting factors into the heap leaching models when they are applied to hazardous constituent leaching would be most beneficial.

Unsaturated flow through deposits drastically affects the flow patterns in deposits. As previously discussed, the flow patterns in waste deposits are extremely complex. All the hydrodynamic equations considered in the literature models are relatively simple one dimensional, plug flow models. More suitable hydrodynamic models need to be

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developed for fluid flow in unsaturated deposits.

The first extension to plug flow models which would begin to incorporate irregular flow behaviour is to include axial dispersion. Levenspiel [1972] describes the use of the 'tanks in series' approach to include axial dispersion. In summary, in a 'tanks in series' approach to a plug flow reactor, the plug flow reactor is modelled as a series of continuously stirred tank reactors. A mathematical analysis of the technique yields the number of tanks required in order to approximate plug flow through the system. Dispersion is included into the model by using fewer tanks than required because fewer tanks tend to erode the plug flow nature by allowing greater degrees of mixing within the system.

The 'tanks in series' model discussed above is a one parameter hydrodynamic model. This means that one parameter is required to account for the non-uniform flow characteristics. More complex, multi-parameter models exist which account for highly irregular flow characteristics. These strategies consider the system to consist of several regions which can be described by plug flow, dispersed plug flow and mixed flow models. Zones which contain stagnant fluid can also be incorporated into these strategies. Levenspiel [1972] discusses the implementation of these techniques.

An alternative approach to dealing with the effect of the complex flow patterns on chemical reactions within trickle bed reactors has been investigated by Funk et al. [1990]; Zimmerman et al. [1987], and, Ng and Chu [1987]. These investigators model the fluid flow at the particle level. To accomplish this they make use of a porous medium model and a fluid distribution model. The porous medium model is used to describe the geometric locations of the particles in the trickle bed reactor. To date, these investigators have only investigated porous media which consist of equi-sized spheres. Using Monte-Carlo techniques, a suitable representation of the geometric locations of the spheres within the trickle bed reactor is obtained. The result of one such simulation is shown in Figure 2-7 (taken from Zimmerman et al. [1987]).

The fluid distribution model is used to determine the fate of fluid which impinges on a single particle in the assembly of particles. Ng [1986] has developed a wetting criterion for particles. For a given flow of fluid onto a particle, this criterion determines whether the fluid will totally cover the particle, which is comparable to ·film flow defined by Lutran et al. [1991], or whether it will be confined to a specific part of the particle -which is comparable to rivulet flow. This information is then used to determine the flow paths of the fluid as it moves from one particle to the next. In this manner the flow patterns of fluid through the trickle bed can be determined. A typical result of such a calculation strategy is also shown in Figure 2-7 (taken from Zimmerman et al. [1987]).

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Figure 2-7. An example of a two dimensional, porous medium model used to simulate the geometrical characteristics of particles in a trickle bed reactor and a typical flow pattern predicted by using the strategy of Zimmerman et al. [1987].

The densely shaded spheres represent complete wetting of the entire particle surface. The spheres with lighter shading over the entire circle are partially wetted. It indicates a liquid film covering more than 50 % of the sphere surface. All unshaded regions on the spheres represent dry areas. Note that the arrows indicate the flow of an isolated liquid rivulet.

Funk et al. [1990] use this strategy to determine the fluid flow patterns and couple this information to a chemical reaction model for reaction in a catalyst pellet. Catalytic reactions are usually steady state reactions and as such are described by suitable ordinary differential equations. The calculations pertaining to the chemical reactions are simplified by making use of an appropriate steady state effectiveness factor. Using this combined model Funk et al. predict overall performance of the trickle bed reactor.

It is very unlikely that such an approach will be able to be applied to leachate generation in granular waste deposits in the near future because of the following limitations. As pointed out earlier, the porous medium model in its present form can only accommodate equi-sized spheres. Although there is no reason why the model cannot be extended to include a size distribution of spheres, the calculation strategy to merely generate the porous medium model will become far more complex. Further, the reactions which take place in waste particles are non-catalytic in nature. Such reactions need to be described

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using partial differential equations. Since these reactions are not steady state in nature, the calculation strategy cannot be simplified by the use of steady state effectiveness factors. This means that the full partial differential equations describing the reactions need to be solved. The computation involved in solving these equations is significant. The computers which would be required to solve the porous media model, the fluid flow path problem and a partial differential equation for each particle in the system makes this approach unattractive. Before such a method is adopted, it is felt that simpler models need to be investigated to determine whether they can be used to solve the problem. Two such simpler models are investigated in the remainder of this thesis. The first model is a macroscopic, lumped parameter model and the second model is a heterogenous columnar model.

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Chapter 3. A Macroscopic, Lumped Parameter Model to Describe Leachate Generation and Mobility in Granular Waste Deposits.

In this work, the first model _investigated, which is capable of predicting leachate generation and mobility within granular waste deposits, is a macroscopic, lumped parameter model. There were two main reasons for investigating a model of this nature. The first reason is due to its inherent simplicity. The macroscopic model considers the deposit as a single reacting entity. As such, it does not attempt to analyze the release of hazardous constituents at the particle level. Instead, it makes use of an overall expression which describes the rate of hazardous constituent release from a small volume element of the deposit. This expression includes the effects of chemical kinetics, hydrodynamic aspects, diffusion and hazardous constituent location on the release of contaminants. This is why the model is termed a lumped parameter model. In effect it assumes that not enough is known about the intrinsic kinetics of the system or about the complex hydrodynamics or even the hazardous constituent location to allow a more rigorous analysis. In many respects, it is this simplicity which makes the model very attractive. In any situation where these aspects cannot be determined or are uncertain, the lumped parameter model can still be used.

The second reason for investigating the macroscopic, lumped parameter approach deals with model accuracy. The lumped parameter model does not require any assumptions with respect to particulate or hydrodynamic aspects. Instead, these effects are included in the experimentally determined model parameter. In effect, the rate of release of hazardous constituents from a waste deposit as a whole is being determined. This is in contrast to more detailed models. More detailed models determine the rate of release of hazardous constituents from the individual particles within a granular waste deposit and then predict the deposit performance. Before the deposit performance can be predicted however, assumptions with respect to fluid flow patterns, fluid saturation and particle wetting need to be made. If any of these assumptions are in error then the accuracy of the more detailed models will be effected. When insufficient information about the deposit is available to make confident choices with respect to these aspects, -the most reliable method may be to make use of the lumped parameter which does not require this information ..

The macroscopic, lumped parameter model was derived by applying a one dimensional fluid continuity equation to the deposit as a whole. The approach adopted is very similar to the one followed by Dixon [1992], the only difference being that Dixon applied the fluid continuity equation to a single particle rather than to an assembly of particles in the form of a waste deposit. The model developed is also very similar to the model of Demetracopoulos et al. [1986] which was discussed in the previous chapter. The main differences between the model developed and that of Demetracopoulos et al. is that the 'rate of hazardous constituent release' term, R, used in the present model was assumed to be described by chemical kinetics rather than by mass transfer considerations. The

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reason for this is that the effects of competing chemical reactions can be investigated with this approach. Realizing that the effects of competing chemical reactions can drastically alter the hazardous constituent release profiles, it was felt that it should be incorporated into the model. The other main difference between the present model and that of Demetracopoulos et al. is that the present model does not make use of hydrodynamic flow equations which describe unsaturated flow. Rather, much simpler 'plug flow' hydrodynamic equations were used. It was realised that the more complete hydrodynamic equations could always be included at a later stage and it seemed more effective to first investigate the potential of the model using the simpler hydrodynamic equations.

The remainder of this chapter ·presents the model derivation. It also discusses an appropriate solution strategy. This is followed by a section which indicates how a time dependent fluid percolation velocity can be incorporated into the solution strategy. The solution strategies have been coded into suitable computer routines and the details of these routines are discussed. Typical results obtained from the model are presented. Some discussion which indicates how the model can be fitted to experimental results is offered, and the limitations of the model are summarised.

3.1 Development of the Equations.

Figure 3-1, a schematic of a lysimeter which is thought to be representative of a real waste deposit, forms the basis of the macroscopic, lumped parameter model. It is assumed that the fluid reagent, A, percolates through the lysimeter and reacts with the solid reactants, Bi, according to the following stoichiometric equation:

n A + I: biBi ... dissolved products

i=l

On a mass basis the stoichiometric coefficient, bi, would represent the mass of solid reactant, Bi, required to react with a unit mass of fluid reagent. This is very often more convenient to use than a conventional molar basis since mass concentrations are more easily determined experimentally, and the 'bi' terms then represent an aggregated elemental behaviour rather than a species balance.

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Figure 3-1. Schematic of a lysimeter which forms the basis for the macroscopic, lumped parameter model.

L

Convection of fluid reagent through lysimeter.

Lysimeter.

The continuity equation for the fluid reactant can be obtained from a statement of conservation of mass. This equation in operator format is:

where NA

(3 -1)

fluid flux through the deposit, including a bulk convective contribution and a diffusive contribution; deposit porosity; deposit saturation; and; defined as the rate of production of fluid reagent A by reaction with species i.

The summation is required to account for the production of fluid reagent A by all the participating reactions.

The equation derived by allowing the rate of production of a solid reactant, Bi, to be described by a kinetic expression which is of variable order with respect to the solid reactant and first order with respect to the fluid reagent is:

( 3 -2)

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where CBi CA ~Bi kBi

mass or moles of the solid reactant per unit volume of solid; mass or moles of the fluid reagent per unit volume of fluid; variable reaction order; and; reaction rate constant.

The reaction rate constant has units, depending on the reaction order term ~Bi' such that the units on the right hand side of the equation are rendered to be mass or moles of solid reactant per unit time per unit volume of solid.

In this analysis, the fluid flux through the column has been assumed to dominated by a convective flux due to the fact that the convective flux usually masks the effects of a diffusive flux. An expression for the convective flux is:

(3 -3)

where u represents the superficial fluid velocity.

Substitution of equations (3-2) and (3-3) into equation (3-1) yields (expressed in one dimensional cylindrical coordinates with axial dependence only):

where t z

time; and; axial position within the deposit.

(3-4)

By assuming that the fluid is incompressible and that the relative void space saturation in the deposit remains constant, which implies that saturation is not a function of fluid velocity through the deposit, the second term on the right hand side of the above equation can be shown to be zero due to the fact that the divergence of the fluid velocity is zero. Thus the equation simplifies to: ·

ac ac n k ccl>sic A A _ ~ Bi Bi A

Col%SatECol at = -u az LJ ( 1-eCol) i=l bi

(3-5)

The initial and boundary conditions which apply are:

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CA ( 0' t) =CAinlBtconc. ( 3 -B)

Note that in equation (3-8) the boundary condition imposed is that the inlet concentration of the fluid reagent to the deposit is constant. It is simple to incorporate the boundary condition which considers the inlet concentration of fluid reagent as a function of time into the model - as long as this function is prescribed. Only the use of a constant boundary condition has been demonstrated in the model development since it is very unlikely for the concentration of fluid reactant entering the column to change dramatically with time.

3.2 Expressin2 the Equations in Dimensionless Form.

It is desirable to express model equations in a dimensionless format. When expressing an equation in dimensionless format, · the original variables are grouped into dimensionless parameters which are less numerous than the original number of variables and which tend to have real physical significance. Reducing the number of variables is advantageous in that it provides results of greater generality, thereby enabling the effects of changing conditions within the deposit to be studied more easily. This is also helpful when attempting to plan experimental work or correlate experimental results [Welty, Wicks, Wilson 1976].

Equations (3-2) and (3-5) to (3-8) can be expressed in dimensionless form by defining the following dimensionless parameters and dimensionless groups:

where

CA a=----c

ArnletConc.

~= z L

( 3 -9 )

(3-11)

33

c. CJ .=_!!2:..

B1 C. B10

.._1=.!:_ T

(3-10)

(3 -12)

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L T=-u •

where L deposit length scale.

DGl= ___ u __ _ u •ec,nCol, sat

(3-14)

(3-13)

c Azni.,tcanc.

CB. 1o

k C+s1 Bi Bi0 L

u*b. 1

( 3-16)

(3-15)

u • is a reference fluid velocity (percolation velocity) which has arbitrarily been set at lm per 24 hours. It is important· to note that the definition of the reference fluid velocity is totally arbitrary and only serves as a convenient manner to non-dimensionalise the results. Also note that:

UPercolation = u (3-17)·

Following on, T is the equivalent of a reference space time for the column; DG 1 is the ratio of the fluid percolation velocity to the reference fluid percolation velocity; DG2 is the ratio of the chemical reaction rate at z=O to the rate of fluid reactant replenishment and DG3 is a dimensionless stoichiometric ratio which indicates fluid reagent strength relative to the solid reactant within the deposit. The rate of fluid reactant replenishment is defined to be the rate at which the fluid in a given volume of the deposit is totally replaced by new fluid due to the convective flux of fluid reactant through the lysimeter.

Equations (3-4) and (3-5) in dimensionless form and in cylindrical co-ordinates are summarised as:

aa DG aa ~ 4's1 -=- 1--"" DG2.(XOB· a-r:' a~ i=1 1 1 (3-18)

with

a ( C 0) =O (3-19)

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ex (O, i:1) =1 (3-20)

daBi 4's1 --=-DG2. DG3 ·CXOs· di:' .l .l l

( 3 -21)

with

a Bi ( C 0) =1 (3-22)

Equations (3-18) and (3-21) represent the progression of reaction within the deposit.

3.3 Solution Strateay.

Equation (3-18) is a first order hyperbolic partial differential equation. Simple finite difference methods and finite element numerical techniques must be used with care when solving hyperbolic problems since the discontinuous nature of the solution gives rise to difficulties when these techniques are used. The discontinuous nature of the solution arises due to the fact that a sharp reaction front, corresponding to the fluid reagent front, moves through the deposit Although it may be possible in some cases to obtain a stable method, it will invariably be very inaccurate. This implies that the solution strategy may calculate a solution but that this solution is incorrect. Note that solution strategies can also be accurate but not stable. This implies that although the correct solution is being calculated, the strategy breaks down before the entire solution is generated. Suitable solution strategies need to be both stable and accurate.

The method of characteristics is a suitable method of solution for first and second order hyperbolic partial differential equations. This method converts the partial differential equation into a set of simultaneous ordinary differential equations. The ordinary differential equations can then be solved using the standard numerical techniques of finite differences or finite elements.

Recall equation (3-18):

acx acx ~ <Psi -=-DGl-- ~ DG2.cxaBi ai:' a~ i=l .l

(3-23)

Using the method of characteristics, which is summarised in Appendix I, the following set of ordinary differential equations is obtained:

Only two of these equations are independent. The two equations used in the solution strategy are:

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dr 1 =...Et_=-___ d_a __ 1 DGl n :E DG2 .a;acjlBi

i=l .l

( 3 -24)

dr1 _ 1 , d~ - DGl

(3-25)

and

da; n cjl - =- :E DG2. <XO' Bi dr1 i=1

1 (3-26)

Equation (3-25) represents the relationship between the time increment and the spatial increment. This highlights the essence of the method of characteristics. By imposing this restriction (of interdependence between two of the parameters) the partial differential equation can be reduced to a simple ordinary differential equation.

A simple expliCit finite difference numerical technique was found to be an adequate method to solve equations (3-26) and (3-21). Equation (3-26) in numerical format is:

Equation (3-21) in numerical format is: •

where j represents a time index.

3.4 Introduction of a Variable Fluid Velocity into the Solution Strategy.

At this point the velocity of the fluid percolating through the column has been assumed to be constant with respect to time. However, fluid velocity through granular waste deposits does vary as a function of time due to various reasons of which periodic rainfall is one example. This has been incorporated into the model in the following manner.

The dimensionless group, DGl, has been redefined as a function of dimensionless time:

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DG1 = fn ('t' 1) (3-29)

Thus equation (3-25) becomes:

dr1 _ 1 d~ - DG1 ( 't1)

(3-30)

Where before the time increment was constant, it now needs to be evaluated using equation (3-30) before each iteration in time. In the case of a functional relationship for the dimensionless group DGl being prescribed, equation (3-30) can be used to determine the dimensionless time increment. However, it is more likely that the functional relationship for the velocity will be prescribed in dimensional terms. (Either in terms of a mathematical function or discretely.) In this case, the followirig equation, derived from equation (3-30), can used to determine the dimensionless time increment:

(3-31)

where (tn+i-tn) is obtained from:

where ll.z L

tn+l

J u(t) dt =Ecol ll.z tn

(3-32)

is the length of a spatial increment within the deposit; and; is the total height of the deposit.

3.5 Suitable Computer Routines for the Model.

Program Model4Dl.PAS and Model4D2.PAS are PASCAL codes which solve these equations as a function of position and time. These codes make provision for the fluid velocity to vary as a function of time. The output of the codes include graphs of concentration versus position and time, with breakthrough curves as a function of time. The breakthrough concentration of any dissolved species in Model4Dl .PAS has been calculated as the amount of that species exiting the column in the time increment over the total original leachable amount of that species in the column. Model4D2.PAS

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normalises all the breakthrough concentrations of the dissolved species relative to the total original amount of the first listed solid species in the program codes. This allows comparison between the relative amounts of the different species which appear in the leachate at the bottom of the column. As an example where such a comparison is useful, consider a waste which contains one leachable hazardous constituent and a large excess of buffering material. Although the fraction of the total buffering material released at any one time may be low compared to the hazardous constituent, the dissolved concentration of the buffer could be equal to, or much higher than that of the dissolved hazardous constituent concentration due to the large initial excess of the buffer material.

A copy of the codes as well as a solution algorithm can be found in Appendix IL

3.6 Verification of the Computer Routines.

The code was verified by subjecting it to a set of tests. In the first test no reaction was assumed to take place. This represents the problem of fluid reactant progressing through a deposit in plug flow. Excellent agreement was obtained between the calculated and analytical fluid profile as a function of time and is shown in Figure 3-2. Figure 3-2 represents the fluid reagent profiles within the deposit at successive time steps, beginning at the left hand side and progressing towards the right hand side of the graph.

Figure 3-2. Comparison of the predicted flow profile with the analytical profile for a lysimeter in which no chemical reactions take place.

1.0 ------------------c c ~ • .. o.e c: •

,..._O:Jcu\~~ ~ - ~be..\

cc - hC'\eQf', u c 0

o.o 0.2 0.4 0.6 o.e 1.0

" 0.6 • • ! ]

0.4 • c • • Q

0.2

o.o

- ' ~ !S A ~ c. tt-oetu1s°' l .... .... r .

'" tif'le.

1 I I ; I I

01...nsionl••• L_....th

The next test involved introducing a single reaction and determining its effect on the

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concentration profiles as the rate of reaction increased. The deposit would be expected to react in a homogenous manner for a very slow reaction, proceed through a transitional phase at intermediate reaction rates and finally react in a zone:.wise manner for fast reaction rates. A zone-wise reaction refers to the case where the reaction is restricted to a narrow band within the deposit. This can be clearly seen in the horizontal rows of graphs in Figure 3-5 where the reaction rate increases from left to right.

The code was also checked to ensure that it could calculate the profiles when more than one reaction was occurring. Several other self-checking strategies were used to ensure that the code was operating correctly. These included the following:

The model was checked to ensure that chemical species were interchangeable. This ensures that the order in which the chemical species are defined in the computer . routines is not important. This is demonstrated in Figure 3-3. In Figure 3-3, the profiles of the first solid reactant are depicted by solid lines while the profiles of the second solid reactant are depicted by dotted lines. (In Figure 3:.. 3 these profiles never touch the X-Axis. Unfortunately the fluid reactant profiles are also depicted by solid lines but they can be identified as the curves which touch the X-Axis.)

The model was checked to ensure that the concentration profiles of two solid species reacting at the same rate were co-incident. This is demonstrated in Figure 3-4. In this figure the dotted lines cannot be identified because they are co-incident with the solid lines.

Kinetic aspects of the model were also checked by ensuring that the model predicted the same profiles for a deposit with a single solid reactant compared to a deposit which contained two solid reactants in equal quantities to the solid reactant in the first lysimeter but which each reacted at .half the rate.

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Figure 3-3. Chemical species in the model are interchangeable.

c ~ .. • .. .. c • u c • "' c ~ ~ ! 0

0.6

a.•

a.a

a.a

So\\a tcoc'c.oi'\t Z Ut'te~eO

a.z 0.4

.l.O

c ~ .. • .. .. c • u c • "' • • ! c ~ • c

! 0

a.6 o.z 0~4 a!6

~~~·Of\ ~ tir.-e. Di ....... ianless U:nowth

Figure 3-4. Profiles of hazardous constituents which react at the same rate are co­incident.

c • .. • .. .. c I u C-

.L.O i

8 0.6 .

• • I

c ~ . c I t

0

Sohd teoc:.t.ol\t. 1. end. 2. (.c:e\~t..)

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3.7 Results and Discussion.

3.7.1 General Behaviour.

In order to determine the- general behaviour of the model and the sensitivity to the model parameters, the following scenario was investigated:

Deposit of 0.5m in length;

Only one solid reactant present;

First order rate dependence in the solid reactant concentration;

Constant fluid velocity set at lm in 24 hours.

These conditions are typical of those used in laboratory lysimeter experiments. In a similar manner, full scale deposit behaviour could have been investigated by merely using appropriate model parameters.

The computer code calculated the dimensionless group DGJ which under the conditions defined is 0.0084.

Figure 3-5 presents the profiles of fluid reagent A (solid curves) and one solid reactant (dashed curves) for all combinations of DG2 = 0.1,1,10 and 100, and, DG3 =0.1,1,10 and 100. Figure 3-6 presents the breakthrough curve of the solid reactant for the same combinations of parameters. Note that in Figure 3-6 each row of graphs have the same Y axis scaling, however the Y axis scaling. changes between the different rows.

For very low values of DG2 the chemical reaction rate is much slower than the rate of fluid reactant replenishment. Under these conditions, most columns would be expected to react in a homogenous manner. This behaviour can clearly be seen in Figure 3-5 by examining the first column of graphs. Only at very high relative fluid reagent concentrations are any solid reactant concentration gradients established. The release of hazardous constituents in columns with low values for DG2 is controlled only by -kinetic factors.

At moderate values for DG2, the type of kinetics depends on the relative fluid reactant concentration. At DG2= 10, non-transient fluid and solid reactant gradients are established for all values of DG3. When DG3 values are greater than 10, the column reacts in a fluid reactant limiting, zone-wise manner.

At high values of DG3 the column reacts only in a fluid reactant limiting, zone-wise manner.

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n . =

0 i f,. =

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Some interesting features of hazardous constituent release can be observed in Figure 3-6. Notice that the breakthrough curves for all columns which react in a homogenous manner resemble an exponential decay function. This is as expected, since a column which reacts in a homogenous manner could be considered as a continuously stirred tank reactor. The concentration profiles for first order reactions which take place in continuously stirred tank reactors are exponential decay functions [Levenspiel 1972]. In contrast the breakthrough curves for columns which react in a zone-wise manner resemble impulse and Heaviside functions (step up followed by a step down function) which are characteristic of perfect plug flow reactors. When the kinetics of the chemical reactions are sufficiently fast for the column always to react in a zone-wise manner, the width of the Heaviside function is determined by the relative fluid reactant concentration. As the fluid reactant concentration increases, the width of the heaviside

· function decreases. In the limit, the heaviside function approaches a Dirac delta as can be seen in the lower right hand corner of Figure 3-6.

3.7.2 Effect of Competini: Reactions.

As previously discussed in Chapter 2, granular waste deposits very often contain more than one reactive component in the matrix. This has a marked effect on the release of the individual hazardous constituents as the following test scenarios indicate.

The effect of a buffering material on the release of a single solid hazardous constituent.

The scenario investigated can be summarised as:

Deposit of 0.5m in length;

One primary solid hazardous constituent and one buffer material present;

First order rate dependence with respect to the solid concentrations;

Constant fluid velocity set at lm in 24 hours.

The parameters . for the solid hazardous constituent were set at DG2conram. = 10 and DG3eontam. =1. .

The combinations investigated are summarised in Table 3-1.

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Table 3-1. Summary of the parameter combinations investigated to determine the effect a buffer material on hazardous constituent release.

Buffer rate constant 100 Buffer rate constant 10 times slower than times slower than contaminant rate const. · contaminant rate const.

10 times as much buffer · DG2Bujfer = 1.00 DG2Buffer - 10.00 as contaminant. DG3Buffer = 0.10 DG3Bujfer - 0.10

100 times as much buffer DG2Buffer = 10.00 DG2Buffer = 100.00 as contaminant. DG3Bujfer = 0.01 DG3Bujfer - 0.01

Figure 3-7 presents the concentration profiles for the above combinations while Figure 3-8 summarises the breakthrough curves.

The concentration profiles in the top left hand corner of Figure 3-7 closely resemble the concentration profiles when no buffer material was present. The breakthrough curves for the same parameter specification show that in this case the buffer material is not sufficiently reactive to affect the release of the solid hazardous constituents; By merely increasing the relative concentration of the buffer material it begins to play a significant role. Alternatively a more reactive buffer material can be used to limit the release of hazardous constituents.

~ .

The buffering material effectively forces the column to react in a more fluid reactant limited, zone-wise manner. This is because the total rate of acid consumption has effectively increased. Further, due to the competition between the solid hazardous constituent and the buffer material for fluid reactant, the hazardous constituent reacts at a slower rate than before and the hazardous constituent breakthrough curves start to resemble exponential decay Junctions.

Notice in the lower row of breakthrough graphs in Figure 3-8 that the solid hazardous constituent persists to breakthrough at large times. This is typical behaviour observed when competing reactions occur.

45

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Extension to more than one reactive hazardous constituent.

Figures 3-9 and 3-10 are sample printouts of typical concentration profiles and breakthrough curves when two hazardous constituents and a buffer material are present. The scenario investigated was a second hazardous constituent of equal amount to the first, but which reacted 10 times slower than the first reactant. These parameters are summarised in Table 3-2:

Table 3-2. Summary of parameters used to demonstrate extension of the model to more than one reactive hazardous constituent.

Contaminant 1. DG2 1 - 10.00 DG3 1 - 1.00 -

Contaminant 2. DG2 2 - 1.00 - DG3 2 - 1.00 -

Buffer Material. DG2 3 - 10.00 DG3 3 - 0.01 -

Figure 3-9. Sample printout of concentration profiles for more than one hazardous constituent.

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48

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Figure 3-10. Sample printout of breakthrough curves for more than one hazardous constituent.

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3.8 Fittin2 the Model to Lysimeter Experiments.

3.8.1 Model Requirements.

The following information needs to be known in order to fit the model to lysimeter results:

The basic chemical reactions which actually take place within the lysimeter;

the effective concentrations of the participating species;

the reaction orders with respect to the solid reactants;

the percolation velocity of the fluid as a function of time; and;

the voidage of the column and the void space saturation.

The level of detail required in the understanding of the basic chemical reactions is to have identified the fluid reagent and the main solid reactants in the system. For example the fluid reagent is usually a dilute acid stream while the solid reactants are leachable heavy metals and buffering components.

49

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The effective concentration refers to the total leachable concentration of any species, which in many instances is not equal to the total concentration of that species. This is caused by a certain portion of the species being unavailable to the leaching process. One method to determine this concentration is to conduct a CSTR leach test until equilibrium is reached. The initial effective solid concentrations of the dissolved species can then be determined by back calculation.

Where the solid reactant is not in excess, a solid reactant order of unity is suggested for the following reasons. The solid reactants are known to be located in a size distribution of waste particles within the deposit. If the deposit contained equi-sized spherical waste particles, comparison of the variable order kinetic expression, equation (3-2), to a 'grain' reaction model indicates that the appropriate solid reactant order in this case would be 2/3. Dixon [1992] has intimated that this order increases as the standard deviation of the size distribution of spherical 'grains' increases and that a reaction order of unity is reasonable. The appropriate reaction order for excess solid reactant is usually taken to be zero, which implies that the solid reactant concentration does not have an effect on the reaction kinetics.

Usually the percolation velocity is set at a constant value. As previously discussed the model can accommodate a variable fluid velocity as long as the functional relationship for the velocity is prescribed.

3.8.2 Fitted parameters.

Each dimensionless group, DG2;, contains a lumped reaction rate constant for the chemical reaction corresponding to that group. These reaction rate constants cannot be determined a priori and so the fitted parameters in the model are the DG2; groups. The reason why the reaction rate constant cannot be determined from bench scale tests is because they include hydrodynamic effects. The hydrodynamic situation in bench scale tests is not comparable to the hydrodynamic situation in a waste deposit or its pilot-scale lysimeter equivalent.

The DG2; groups are fitted by comparing the breakthrough curves from the model to experimentally determined breakthrough curves from lysimeters. A good method to optimise the agreement between the model and experimental results is to use a simplex search technique to determine the best values for the fitted parameters.

3.9 Limitations of the Model.

The macroscopic, lumped parameter model does have several limitations due to its inherent simplicity. The first limitation of the model is that it can only be used to extrapolate to deposit proportions and in time for deposits which contain identical wastes and which exhibit identical hydrodynamic characteristics to the ones observed in the

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lysimeter. This implies that a separate lysimeter experiment needs to be conducted for each waste stream and hydrodynamic situation investigated. This is a severe limitation considering the expense and time involved with lysimeter experiments.

The second limitation is that the model can be used only in situations where each solid reactant is released at a single overall rate. Often, particles which have most of the solid reactant concentrated onto the surface of the particle, can also have some of the solid reactant distributed in the bulk of the particle. The solid reactants in the two regions very often exhibit different rates of release.. The first rate of release is due to the release of the solid reactants on the surface. Usually this rate of release is much faster than that of the release from within the bulk of the particle due the added diffusional resistances of the fluid reactant into the particle.

The model cannot be used to determine the individual contribution of the intrinsic chemical kinetics, the hydrodynamic aspects or the hazardous constituent location on the release of hazardous constituents. This is a direct consequence of using the lumped parameter approach. Since one aim of this work is to eventually be able to engineer better waste deposits, it is critical to be able to determine these individual contributions.

For these reasons it was deemed necessary to investigate more complex models which would begin to address the limitations of the macroscopic, lumped parameter model. In effect this implied investigating models which describe the release of hazardous constituents at the particle level. This is the focus of the remainder of this thesis.

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Chapter 4. A Summary of the Chemical Reaction Model Applicable to Single Particles as Developed by Dixon [1992].

The investigation into the macroscopic, lumped parameter model revealed a need to describe the release of hazardous constituents at the particle level. As discussed in Chapter 2, Dixon [1992] has developed a chemical reaction model for investigating the leaching behaviour of precious metals from ore particles. His model is sufficiently detailed to include the effects of diffusive and chemical reaction kinetic resistances, competing reactions and precious metal location within the particle on the leaching behaviour. Since these considerations are similar to the ones encountered in leaching of hazardous constituents from waste deposits, it was felt that Dixon's model should be investigated to determine its applicability to modelling contaminant leaching from waste particles.

This chapter presents the details of the investigation into the applicability of Dixon's model to a single waste particle. This involved determining whether or not the model developed by Dixon could be used without modification. For this reason, this chapter summarises the model development followed by Dixon [1992]. Once it was determined that Dixon's particle scale model could be used, an appropriate solution strategy for the model was investigated and implemented. The computer routines which implement the solution strategy have been rigorously checked against the results obtained by Dixon. These details form the reminder of this chapter.

4.1 Development of the Equations.

Figure 4-1 depicts a porous, spherical particle of radius R which is submerged in fluid reactant and which contains small amounts of solid reactant deposits. Dixon [1992] assumed that these solid reactants, Bi, are dissolved by a single fluid reagent A. This is represented by:

n A + :E biBi .... dissolved products

i=l

As in Chapter 3, the continuity equation for the fluid reactant can be obtained from a statement of conservation of mass. The continuity equation applicable to a single particle is:

(4-1)

52

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where NA €0

rAi

fluid flux into the particle; particle porosity; and; defined as the rate of production of fluid reagent A by reaction i.

I

As before, the summation sign is required to account for the production of fluid reagent A by all the participating reactions.

Figure 4-1. Schematic diagram of a porous, spherical particle of radius Rand a graph showing the concentration gradients within the particle. (taken from Dixon [1992]).

0 Particle radius, r R I I

Co ~, Cso

.,, c:

"' 0

w g "' .'.. c: ~ ..

~ u c: 0 u "'

,. .

~· I

0 Part! cl e radius, r R

Dixon made explicit provision for different kinetics for those reactions which occur in the bulk of the particle compared to those which occur on its surface. Considering first the reactions which occur within the pores of the particle, Dixon assumed that the reaction kinetics can be described by an expression which is of variable order with respect to the solid reactant and first order with respect to the fluid reagent. This expression. can be summarised as:

where cpi

qCpi = k C<P~1 C dt - pi pi A

(4 -2)

mass or moles of the solid reactant in the pores of the particle per unit mass of solid;

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CA mass or moles of the fluid reagent per unit volume of fluid; and; ~i reaction rate constant.

Here the reaction rate constant has units, depending on the reaction order term ~Bi' such that the units on the right hand side of the equation are rendered to be mass or moles of solid reactant per unit time per unit mass of solid.

In situations where the kinetics of any species on the surface of the particle is different to the kinetics of that species in the bulk of the particle, another kinetic expression will be required. The kinetic expression adopted by Dixon can be summarised as:

where csi

dCsi 3ksic!11cA --=-

dt R Po (l-e0 ) (4-3)

mass or moles of the solid reactant on the surface of the particle per unit mass of solid; mass or moles of the fluid reagent per unit volume of fluid; radius of the particle; ore density; and; reaction rate constant.

The following equation makes it a bit easier to see how this expression was obtained:

Mass of pa+ticle dCsi --k 4's1

Area of particle -cit- sicsi CA (4-4)

Thus the units on the left hand side of the equation are mass or moles of solid reactant per unit time per unit area of panicle. Therefore, the units of the reaction constant, ~i' depending on the reaction order term ~si' are such which render the units on the right hand side of the equation to be mass or moles of solid reactant per unit time per unit area of the panicle.

It is important to note that if the kinetics of the species on .the surface of the particle are not significantly different from the same species within the bulk of the particle, that the requirement for equation (4-3) is obviated.

Substituting equation ( 4-2) into equation ( 4-1) gives:

n '\!· NA - po ( 1 -eo) ~

i=l ( 4 -5)

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Dixon assumed that only a diffusive flux of fluid reactant entered the particles and made use of Fick's law to describe this flux. Substituting Fick's law into equation (4-5) and expressing the equation in spherical co-ordinates with radial dependence only gives:

(4-6)

The initial and boundary conditions which apply are:

CA (I, 0) =0 (4-7)

( 4-8)

ac · a: (0, t) =O (4-9)

It is important to note that equation ( 4-8) effectively implies that no film mass transfer resistances are being considered. This assumption is only valid where the film mass transfer is fast compared to the diffusion of the fluid reactant into the particle and the reaction of the fluid reactant within the particle.

4.2 Expressini: the Equations in Dimensionless Form.

Equations (4-3) and (4-6) to (4-9) can be expressed in dimensionless form by defining the following~ dimensionless parameters and dimensionless groups:

c CA IX=--....:'.!. (4-10) IX - b (4-11) b--c CAo Ao·

c. c. (J .=_.E3_ (4-12) (J . = __!!1:_ (4-13)

pi c. Sl. C. Pl.o Sl.o

I (4 -14) De,.t

( 4-15) ~=- 't'= R e R 2

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(4-16) (4-17)

( 4 -18) ( 4 -19)

.Bi represents a dimensionless stoichiometric ratio which indicates the reagent strength relative to the grade of solid reactant i. In a particle of given porosity which is in contact with a fluid reactant of concentration a= 1, a value of .Bi = 1 would imply that there is sufficient fluid reactant within the pores of the particle to completely react all of the solid reactant.

Ai represents the fraction of solid reactant residing on the surface of the particle.

Kpi and Ksi are ratios of the reaction rate of solid reactant i within the particle pores and on the particle surface, respectively, to the porous diffusion rate of fluid reactant A. In an investigation into the effects of flow, diffusion and heat conduction on reactor performance, Damkohler recognised the importance of four dimensionless groups. The second of these is the ratio of the chemical reaction rate to the rate of diffusion [Aris 1975]. Thus Kpi and Ksi correspond to Damkohler numbers of the second type. These ratios can be identified a bit more easily if the equations are written in the following format:

p (1-e) kpic:1:cA

bi Kpi=~~~~~~~-

DeACA R2

(4 -20) ( 4 -21)

The equations in dimensionless form and in spherical co-ordinates are summarised as:

(4-22)

with

a (CO) =O (4-23)

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( 4 -24)

aa. ~ (0,'t) =O (4-25)

(4-26)

with

(4-27)

d A <l>si a si Ksi t' i a si Cl b --= - --,....----d't )..i

(4-28)

with

asi (0) =1 (4-29)

Equations (4-2~) to (4-29) represent the progression of the reaction within a single particle.

4.3 Suitability of Dixon's Model to Hazardous Constituent Leaching From Waste Particles.

The development of the equations used in Dixon's particle scale model do not include any aspects which are unique to precious metal leaching from ore particles. The same equations would have been determined if the leaching of hazardous constituents from a waste particle had been considered. For this reason, Dixon's equations can· be used without modification to model hazardous constituent release from a waste particle.

4.4 Solution Strategy.

Equation (4-22) is a second order parabolic partial differential equation. A suitable solution strategy, which would be both stable and accurate, was desired to solve the set of equations. The Crank-Nicolson formula, which is an implicit finite difference method, is a suitable solution strategy since it is both unconditionally stable and sufficiently accurate [Crank 1975].

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The Crank-Nicolson approach uses a Taylor series expansion of the concentration function to obtain expressions for the partial derivatives. These are:

where

02N I a. 1 .-2cx . . +a. 1 . .... .. .l+ ,] .l,J .I- ,]

a~2 i,j <.d~)2

i is a spatial index and j is a time index.

(4-30)

(4-31)

Crank and Nicolson [1947] suggested that a better approximation for the above quantities would be the average of the quantities evaluated at times j and j + 1. This yields the Crank-Nicolson formulas for the partial derivatives:

(4-32)

and

::12N 1 a. .-2cx .. +ci. . a. . -2cx. . +a. . _er_ ... I· ... _. < .l+l,J .l,J i-1.1 + .l+l,J+l .l,J+l .i-1.1+1)

a~2 .l,] 2 <.d~)2 (.d~)2 (4-33)

Using these formulas, equations (4-22), (4-26) and (4-28) were converted to numerical equations.

Equation (4-22) in numerical format is:

fori=O

(4-34)

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and for i< >0

N 2 ~ (a~)2 .+ -·-ex ._1 . (-i+l) +ex· · (2i+ ~Ki (a~) CJi j-2i a't ) exi+l,J' ( 1- 1)

.l • J i, J i =l p • (4-35

The reason for two equations being required is due to a singularity which exists at the origin in equation ( 4-22). This problem was overcome by noting that total symmetry exists at the origin and thus equation (4-22) can be expressed in cartesian co-ordinates at this point. Note that the canesian co-ordinates are only valid at the origin. The equation used to derive eq!Jation (4-34) is:

(4-36)

The numerical format of equation (4-26) is:

oiJ+1- 0 iJ KPP (~ +~ , a 't , =- 2 ( 1-A.) o i.Jex i,J o i,J+1ex i,J+1) (4-37)

The numerical format of equation (4-28) is similar to equation (4-37).

4.5 Suitable Computer Routines for the Model. -

Program Model2D2.PAS is a PASCAL code which solves these numerical equations as a function of position and time. The output of this code includes a graph of the solid and fluid reagent profiles within the particle as a function of time and a graph of the fractional conversions as a function of time. The fractional conversion is defined as the fraction of a particular solid reactant species which has been released.

A copy of the code can be found in Appendix III.

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4.6 Verification of the Computer Routines.

The computer routines written needed to be checked to determine whether they operate correctly. One method to check the routines would be to reproduce the results presented in Dixon's thesis. To this end, all of the results presented in Chapter 1 of Dixon's thesis which involve concentration profiles and fractional conversions as a function of time have been reproduced. To demonstr(j.te this, Figure 4-2 is a series of graphs produced by Model2D2. These graphs can be compared to those found in Figure 4-3 which are the graphs presented by Dixon for the same parameter specification.

Further comparisons between the results predicted by Model2D2 and Dixon's work can be seen in Figure 4-4 and 4-5; and; Figure 4-6 and Figure 4-7.

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..... 0 0 II

cQ

-II cQ

8 -II cQ

l Figure~r~~----~----------...._ __ ...., ______ .,.

I~ .::lr=l

1.0 J~!.f [~!!~?!'!~~'~:~~~~::::·····. ·· .. a e S.hcl · .. -.. · .. ·._ ._ ·.. .. ·.. .. · 1-'-• · .. · .. · ............... · .. ' .... ·· .. :<::;<:::::::::·, \

0.4- ........

. ..l.0....1 ~t ~iiiiiiiijfiiiiiiiiiiii~~~~::::~-:~.:.~·;;i~~~:;;:~i2i2~i;;~;;;;

a.oJ 0.2 a.4 a.6 , a.o i.o 0

1.0

o.e

0.6

0.4

o.a

a 0 I • I

o.

I

o.e

a.6

0.4

a.a

a.a oJ

I

Dimensionless Radius, ~

lwnm•••••• .............................. . t:::: ::: :::::::::: ::: ::::: ::: : :.:.:::::: :: .... ~:::: :~.-.· .......... .

··· ... ·· .. ·· .....

..

Dimensionless Radius,~

a.a a.4 0.6

Ar=0.0316

a.a

.. _ .. ··-· .... 1.0

Ar=0.001

o.e

Dimensionless Radius, ~

K =100 p

~ I

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Figure 4-3.

{1 = 0.01

{1 =

p = 100

The corresponding concentration profiles to Figure 4-2 presented Dixon. (Figure 1-3 taken from Dixon's Thesis.)

= 0.01

'JI ,~

6r

b. a.a

0.1

a O.t

O.J

6T • ~.le 'JI ...-_-_ ---""-""·---• ....,_,..,_,.,_..,_.;;;_.;.._ --_,,._,,._,.,_;-_-,_..,_-_-_.,

---------------------·-· ---·--·--·---···------·----------·-----------·------·-------------------:;::~{:_ ~~~:~~:.;~~:~-;_ ~~:-:-:.~:.

0.1

a 0.4

OJI+._. __ _,, ____ ~---------~ '14 C.• 0.1 0.1 •.Q

-----------

'. : ~:,~:::-~~:;;;~~ !u

0.0 I c~ ~..l :.• r:.s e.1 1 .o

Dimensionless rocius, f

= 100

:: g:;;:~~~j ------------------------

0.I ... ::::· ... ·.:::·:.:::· .. ·.:::::·.:-

0.1

C.I

C.& ;;~;;~;~~~~~~~~~~~~~~~~~ C.•

0.2

O.I ·--------. ••••••••••••

------------- ... -- ....... o.• ··--......................................

o.: :iiiiiiiiiiiiiiiiiiiiii~-~ ~.o 4------------i OJI Q.J o.• C.I Cl 1.0

QT' - 0.01 t.0 .... _-_-_ .. _ .. _. .................... -....,---, -.

" C.I ··-··­ .

0.1

··-0.4

O.J

o.o ~;;;;;;:=;;;G;;;;;;.;;:::::;.;~~~:J o.o o~ o.• e 1 0.1 ,_o

Dimensionless radius. ~

62

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Figure 4-4. Fraction conversion profiles predicted by Model2D2 for the parameters as Indicated in the Figure.

1.0

O.B

c 0.6 0 ... Ul I. QI ::> c 0 CJ

0.4

0.2

0.0...f!!:~~~~~~~~+--~~~-t-~~~~r-~~~1

o.o 2.0 4.0 6.0 a.o J.0,0

DiMensionless Reaction TiMe <KappaJ>•Beta•Tau>

Figure 4-5. The corresponding fractional conversion profiles to Figure 4-4 presented by Dixon. (Figure 1-4 taken from Dixon's Thesis.)

1.0 -.---~~~~~~~-:::=-~~~~~~~~~---,

x

c 0.8 0 (.J) L

GJ a 5 > . c 0 u 0.4

0 c 0 0.2

-+-' u 0 LQ.O ~::;:::;:: ........ ......,...,...,.......,....,...,...,...,..,....,...,...,...,..,....,...,...,...,..,....,.."T"T""M'"T"T"T"",...,..,.""T""l"'"T"M-:-TT"M:-r1

Li_ 0 2 4 6

Dimensionless reaction

63

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Figure 4-6. Fraction conversion profiles as a function of the variable order power predicted by Model2D2.

0.6

0.4

0.2

o.o"""f-~~~--r--~~~-t-~~~~t--~~~-+1 ~~~--1 0.0 6.0 .l<!.O .lB.O <!4.0 30.0

Dil'lenSionless Reaction TiMe <Mith r~t to RXN 1 > CKaPDaPl*Betal*Taul

Figure 4-7. , The corresponding . fractional conversion profiles as a function of variable order power to Figure 4-6 presented by Dixon. (Figure 1-9 taken from Dixon's Thesis.)

-co.a 0 (J) ~

~ 0.6 c 0 .u 0.4

0 c Q0.2 ~

(;.)

0 ~a.a o 10

Dimensionless

Kp = 100 p = 1

20 reaction time,

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Due to the excellent agreement between the results of Model2D2 and those presented by Dixon, the routines of Model2D2 can be used with confidence.

4. 7 Application of the Model.

The chemical reaction model at the particle level is not that useful in itself. The model as it stands only describes the progression of the reactions in a single panicle. It is very unlikely that the progression of the reactions within a single solitary particle will be required. Further, the boundary condition used, equation (4.8) or (4-24), implies that the fluid concentration in contact with the surface of the particle is constant. The only situation where this would arise is where a particle is submersed in an infinite amount of fluid and where mass transfer resistances are negligible.

· More realistic situations are when many particles are associated with a finite volume of fluid. Such situations correspond to a CSTR experiment in which the leaching behaviour of a single size class or a size distribution of particles is investigated. Equally, a volume element of a waste deposit could be considered as an appropriate size distribution· of particles associated with a finite volume of fluid. In this case the fluid would be the fluid in the void spaces between the particles.

In these situations, as the chemical reactions within each of the particles progress, fluid reagent will be consumed which will cause the bulk fluid concentration, that is the concentration of the fluid which surrounds the particles, to decrease. This dropping bulk fluid concentration is the appropriate boundary condition which should be used in particle scale model. In effect, this implies that a suitable boundary condition, which would replace equation (4-8) or (4-24), needs to be developed which will account for the decrease in the bulk fluid reagent as a function of time.

It is important to note that a partial differential equation, corresponding to equation (4-8) or (4-24), will be required for each particle size considered when the leaching behaviour of a size distribution of particles is investigated. The reason for this is that the rates of conversion of different sized particles will not be the same. Suitable dimensionless groups, which are defined in terms of a single reference particle size, need to be investigated. Lastly, appropriate solution strategies for the combined solution of the set of partial differential equations, which is comprised of a partial differential equation for each particle size, and the coupled boundary condition need to be determined. These aspects are considered in the following chapter.

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Chapter 5. A Model to Describe Leachate Generation from Granular Wastes in a Continuously Stirred Tank Reactor Experiment.

The continuously stirred tank reactor (CSTR) model describes the increase in the hazardous constituent concentratic;m and the decrease in the fluid reagent .concentration in the bulk fluid of a CSTR type experiment. This is· achieved by linking the particle scale, chemical reaction model, presented in the previous chapter' to an appropriate mass balance equation for the bulk fluid reagent concentration.

The appropriate mass balance equation is developed initially for equi-sized particles submerged in a finite volume of fluid reactant. In a CSTR experiment which contains a size distribution of particles, the release of hazardous constituents from each size class of particles needs to be determined before the overall release of hazardous constituents for the system can be calculated. This implies that a partial differential equation, corresponding to equation (4-22), will be required for each size class of particles. Before these differential equations can be used, the appropriate parameters for each size class of particles need to be determined. For this reason, a section which discusses model parameters as a function of particle size, has been included. This is followed by the development of a suitable mass balance equation for the consumption of fluid reagent in a CSTR experiment which involves a size distribution of particles.

An appropriate solution strategy for the model has been investigated and implemented. A case study has been used to illustrate the general behaviour of the model and the sensitivity of the model to particle size distributions as well as to hazardous constituent distribution within each solid particle. The following section discusses how the model can be fitted to typical CSTR data. Lastly the applications and limitations of the model are summarised.

5.1 Development of the Mass Balance Equation for the Bulk Fluid Reaa:ent in a CSTR which Contains Equi-Sized Particles.

Figure 5-1 depicts a few equi-sized spherical particles in a beaker of fluid reagent. It is assumed that the fluid reactant diffuses into the particles and reacts with the hazardous constituents which then enter the fluid phase.

The fluid reagent mass balance replaces the boundary conditions used in the model of Dixon [1992]. Referring to equations (4.22) to (4.29), note that equation (4-24) is a boundary condition which sets the bulk fluid concentration in contact with the particle at a constant value. This boundary condition needs to be replaced due to the fact that the bulk fluid reactant concentration drops as the fluid reactant diffuses into the particle.

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Figure 5-1. Schematic· of a few equi-sized spherical particles submerged m a well stirred beaker of fluid.

0 0 0

Equi-sized Particles.

Beaker.

A mass balance equation which relates the consumption of the fluid phase reactant to the bulk fluid reactant concentration is:

VPart. Po ( 1-Eo) f dCsi -D 'VC I 3 VPart. =V . bi i=l dt e A R R Liq.

where V Part.

Vu q.

is the total volume of the particles; and; is the total volume of fluid reactant.

(5-1)

Note that the first term in the above equation represents the consumption of fluid reagent due to chemical reactions which take place on the surface of the particles. The second term represents the fluid reagent diffusing into the particles. This quantity is calculated as the product of the diffusive flux into a single particle (the diffusive flux being defined by Fick's Law), the surface area of a single particle and the number of particles in the system. The number of particles present in the system is determined by dividing the total volume of the particles by the volume of a single particle. The fluid reagent which diffuses into a particle is continually being consumed by the chemical reactions taking place within the pore volume of the particle.

The same equation expressed in dimensionless terms is:

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~ cPsi aa. I aa. bulk - ."-'Ks Osi CX.bulk-3 ai: ~=l =V a

i=l i ~ ~ (5-2)

where

v . V = Liq.

Eo VPazt. ( 5-3)

As previously discussed, the chemical reaction model derived in Chapter 4, applies to a single particle. Equation (5-2) is a suitable boundary condition for equi-sized particles submerged in a finite volume of fluid reagent. This boundary condition, in conjunction with the chemical reaction model for the single parti~le, can be used to simulate both the concentration profiles of the solid reactants and fluid reagent within the particles as well as the bulk fluid phase concentration as a function of time.

5.2 Model Parameters as a Function of Particle Size.

As previously discussed, in order to simulate the progression of reactions in a size, distribution of particles, the chemical reaction model needs to be applied to each individual size class. The overall progression of the reaction for the system is then obtained by integrating the results of the individual size classes over the distribution of particles in the ·system.

Before the chemical reaction model cap. be solved for each size class of particles, the model parameters applicable to each size class need to be determined. Two different approaches to defining the model parameters as a function of particle size can be used. In the first approach, model parameters are fitted to only one size class of particles and the parameters of all the other size classes are related to it. The assumptions behind this approach and the resulting relationships for the model parameters as a function of particle size aie discussed in the next section. In some cases, particles in different size classes exhibit sufficiently different properties to preclude any simple relationships between them. In these cases the model parameters need to be determined for each size class individually.

5.2.1 Determination of the Model Parameters Applicable to Precious Metal Leachin2 with Respect to a Reference Size Class of Particles.

Dixon [1992] defined a set of relationships for the model parameters_ in terms of a reference particle size. The parameters of the reference particle size, which are denoted as barred quantities and which need to be specified, can be summarised as:

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Dixon's work [1992] was specific towards the extraction of precious metals from ores and so made use of information with regard to ore preparation to determine appropriate relationships for the model parameters. In summary, Dixon made the following assumptions with respect to ore preparation:

Only the surface fraction, Ai, is affected by crushing, and not the total extractable grade, CEiO• or any other parameter; .and;

A.i is proportional to the ratio of the particle area to the particle volume.

Using these assumptions, the following relationship was obtained:

where

where Rk R

). . ). . =-2

1.k e k

( 5-4)

( 5 :-5)

radius of particle in size class k (k€{1..M}); and; radius of the reference particle.

ek is a dimensionless total particle radius. It is important to note that the dimensionless total particle radius can be greater than one. This occurs when the radius of the reference particle is smaller than the radius of the particles in size class k.

Dixon proceeds to determine relationships for Kpi• Ksi and T in terms of the corresponding reference class parameters combined with Ai and Ok.

5.2.2 Determination of the Model Parameters Applicable to Leachina= of Hazardous Constituents from Waste Particles with Respect to a Reference Size Class of Particles.

The assumptions which Dixon made with respect to ore preparation to determine the model parameters as a function of particle size do not hold for waste particles. The reason for this is that Dixon's assumptions are based on his previous assumption of the solid reactants being present in the form of discrete inclusions within the porous particle. Further, the only reason that the surface concentration of the solid reactants will increase with decreasing particle size is due to the fact that more inclusions stand a chance of

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falling on the external· surface area of smaller particles.

In contrast, the hazardous constituents in waste particles are usually not restricted to discrete inclusions. Also, the concentration of the hazardous constituents on the surface of particles in known to be enhanced in smaller particles in some cases [von Blottnitz 1994; Van Craen et al., 1983]. (These aspects have been discussed previously in section 2.1.1.) For these 'reasons, appropriate relationships for the model parameters with respect to a reference particle size which would be applicable to waste particles need to be determined.

It has been assumed that the initial hazardous constituent concentration within the particles, Cpio' is the same for all particles. In contrast, the initial surface hazardous constituent concentration, Csio' is known to be a function of particle size [Van Craen et al. 1983]. In summary, it has been assumed that all properties of the particles, except the surface concentration and thus the total extractable concentration, remain fairly constant over the range of particle sizes. In a manner similar to Dixon, the reference size class's parameters have been denoted as barred quantities. The reference size class parameters which need to be defined are identical to. those of Dixon.

It is not yet possible to predict the surface hazardous constituent concentration as a function of particle size from purely theoretical arguments. Instead this information needs to be determined from hazardous constituent location analyses for the particle sizes of interest or estimated from existing hazardous constituent location data. This information must be specified in a parameter which is defined as the ratio of the · hazardous constituent concentration on the surface of the particles to the hazardous constituent concentration within the particles:

( 5-6)

where C hazardous constituent concentration of species i on the surface of the si,O,k particle in size class k; and;

C hazardous constituent concentration of species i in the pores of the particle pi,O,k in size class k.

Once the S-i(ak) values have been specified, sufficient information is known about the system to formulate suitable functional relationships for the model parameters. This i~ demonstrated for the A.ik parameter, which represents the fraction of the solid reactant on the surface of the particles:

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(5-7)

In a similar manner, relationships for the other model parameters can be determined. These relationships can be summarised as:

( 5-8 ) (5-9 )

(5-10) (5-11)

( 5-12)

Dixon [1992] has shown that if it can be assumed that the chemical species within the particle would react to the same extent as the species on the surface of the particle, if both were exposed to the same fluid reactant concentration for the same time, then the surface parameters take on the form:

( 5 -13) ( 5-14)

This information can be used to eliminate the need to define Ksi· Thus equation (5-9) could be written as:

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A, . r1, <l>pi

_- 1 ("1r:) a Ksi -K_pi--=- -=- 'Clk

/I: 1-A.i <;i ( 5 -15)

5.3 Extension of the Bulk Fluid Mass Balance Equation to Incorporate Fluid Reactant Consumption from a Size Distribution of Particles.

Equation (5-1) is a bulk fluid reactant mass balance equation which accounts for the fluid reactant being consumed by equi-sized particles. This equation can be extended to apply to a size distribution of particles by summing the fluid reactant consumed by the different size classes. This can be summarised as:

(5-16)

where V Part,k is the total volume of particles in size class k; and; M number of sizes classes.

This equation re-expressed in dimensionless format is:

~ [- ~ y Part,k o"'~i ,.., - 3Y Part,k ( aa.) I ] - VLiq Ksi,k s1,k ""bulk 2 a~ k ~=1 -

k=l i=l e2k a e v uk o Part.

(5-17) where

v y = Part,k Part,k

VPart.

(5-18)

where V Part,k total volume of particles in size class k; and; V Part . total volume of particles in the reference size class.

Equation (5-17) is a suitable boundary condition which applies to a size distribution of particles. This boundary condition, used in conjunction with a suitable partial differential equation, equation (4-22), for each size class of particles can be used to simulate the concentration profiles within all of the particles in the system and the bulk fluid reagent concentration as a function of time.

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5.4 Solution Strateay:

The system of equations which define this model are identical to equations (4-22) through to (4-29) except that the one boundary condition, equation (4-24), is replaced by equation (5-17). This equation was incorporated into the solution strategy using an implicit finite difference technique.

As it has already been pointed out, in order to simulate chemical release from a size distribution of particles, the chemical reaction model needs to be applied to each and every size class of particles. The solution strategy adopted for the CSTR model makes use of the solution strategy used to solve Dixon's model and is summarised in Figure 5-2.

Figure 5-2. Summary of the Solution Strategy used in the CSTR model.

J Within each time iteration: I ~ J,

Guess the bulk fluid reactant concentration. I ' ~

Apply the solution strategy adopted to solve Dixon's model to calculate the fluid and solid reactant gradients in the particles for each size class 1 to M.

Use the bulk fluid mass balance equation, equation (5-15), to calculate the bulk fluid reactant concentration.

~ Iterate until the calculated bulk fluid reactant concentration approximates the guessed fluid reagent concentration.

I

5.5 Suitable Computer Routines for the CSTR Model.

Programs Model5El.PAS and Model5E2.PAS are suitable computer codes for the CSTR model. Model5El .PAS is a code which assumes a reaction order of unity with respect to the solid reactant while Model5E2 .. PAS can accommodate a variable reaction order.

Copies of the code as well as solution algorithms can be found in Appendix IV.

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5.6 Verification of the Computer Routines.

As before, the computer routines were rigorously checked to ensure that they were operating correctly.

The first test applied was to use Model5El to predict the concentration profiles within a single size class of particles with a large excess of fluid reagent. Because of the large excess of fluid reagent, its concentration would not be expected to drop significantly during the CSTR experiment. Such a constant bulk fluid concentration boundary condition corresponds to the boundary condition used in the development of the chemical reaction model described in the previous chapter. Thus, Model2D2, using the same parameters as used in Mode15El, should predict the same profiles as Model5El for an experiment of this nature. This is demonstrated in Figure 5-3 and Figure 5-4.

Several other self-checking_ strategies were employed to ensure that the routines were operating correctly. The most important strategies used included the following:

The model was checked to ensure that it would predict the same concentration profiles for a given size class of particles irrespective of the order in which the size class of particles was entered into the program.

The program was checked further to ensure that if the average particle size in two 'different' size classes were identical that the code would predict identical concentration profiles for both size classes.

The fluid mass balance equation was checked to ensure that it was operating correctly by defining several 'different' size classes of particles all to contain the same sized particles. As long as the sum of the volume fractions of these size classes remain constant, the overall fluid reagent consumption should remain constant The computer routines predicted this expected behaviour.

The fluid mass balance equation was further checked to ensure that as bulk volume of the fluid was decreased in a series of CSTR experiments that the resulting bulk fluid phase concentration of the reagent would decrease.

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Figure 5-3.

Figure 5-4.

Concentration profiles predicted by Model5El for a single size class of particles with a large excess of bulk fluid reagent

Bet•1 J..ooo; K-0.:,eJ. ioo.ooo: L....mae.1 o.ooo; orcter.l i.oo; GOT o.03.16 Beta2 l..000; K..,.,82 100.000: L..-82 o.:soo; Orcltlr2 1.00

1.o~!!!!!!~::::'~~~~~~~S:::~::::""'""7:-

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• ; ~ 0.4 c ~ ~

' 0 0.2

a.OJ;~~~~~~~~~~~:;;~~~~~~~~,.,.::~~ o.o o.;;i 0.4 0.6

Dinen.5ionless Radius

Concentration profiles predicted by Model2D2 using the same parameters used in the simulation used to generate Figure 5-3.

-1202 Betel. 1.000; Kanoa.1 100.000; L..mc:ta1 0.000; Or<Mr.1 J..CXJ: GOT 0,0:JJ.6

Bet82 1.000; K..,.,e2 100.000: L....ixta2 O.:SOO: Orcltlr2 J..00

1.0.,,...,...,,,,,,, ..... """,,,.,. .... ~~.,.,~~===,.....-=-~~

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• • • c 0.4

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0 0.2

o.o o.;;i 0.4 0.6 1.0

OittenSionless Radius

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5.7 Results and Discussion.

5.7.1 General Behaviour.

In order to determine the general behaviour of the CSTR model, the following scenario, representative of a typical bench scale CSTR experiment, was investigated:

Volume of fluid reactant = ll;

Total volume of solid particles = O. ll;

Size distribution of the particles used is summarised in Table 5-1 and shown in Figure 5-5;

-

Only one solid reactant present;

First order rate dependence in the solid reactant concentration;

r1 k used is summarised in Table 5-1 and shown in Figure 5-6; ,

Table 5-1. Size Distribution and r1 ,k used in the Analysis.

Size Class Average Particle % r1,k Number. Size in Size Occurrence.

Class. (mm)

1 9.5 0.252 1.2 2 8.5 0.428 1.2 3 7.5 1.045 1.3 4 6.5 2.564 1.3 5 5.5 6.191 1.4 6 - 4.5 14.061 1.4 7 3.5 27.105 1.6 8 2.5 34.247 1.8 9 1.5 13.846 2.3

10 0.5 0.260 5.0

Note that the size distribution of particles included in Table 5-1 is representative of a log-normal size distribution. Also, the r1,k values were obtained by assuming them to be inversely proportional to the radius of the particle. The equation used to generate the r1 k values used in Table 5-1 can be summarised as: ,

( 5-19)

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where Rk is the average radius of the particles in size class k.

This corresponds to the situation in which infinitely large particles exhibit identical surface and bulk 'grades' of hazardous constituents. Also, the ratio of the surface to bulk grade for the particles in size class 10, which have an average radius of 0.5mm, has arbitrarily, for demonstration purposes, been chosen to be 5. In retrospect, a better relationship would have been:

( 5-20)

The reason why this relationship is superior to equation (5-19) is because it corresponds to the case where infinitely large particles exhibit a negligible surface grade of hazardous constituents compared to the bulk grade of hazardous constituents. This situation is far closer to what would be expected in reality. The reason for this is because the external surface area of a particle increases in proportion to the square of the radius while the volume of a particle increases in proportion to the cube of the radius. Thus infinitely large particles will have a negligible surface area compared to the volume of the particle. Hence the surface 'grade' of the hazardous constituents will be negligible. The ratio of ·the surface grade of hazardous constituents to the bulk grade of hazardous constituents for the reference size class of particles in equation (5-20) has once again arbitrarily been chosen for demonstration purposes to be 5.

Figure 5-5. Size Distribution of Particles used in Analysis

50 ·································

40 Q) () c • Q)

'.:i 30 () ()

0

* 20

• 10

o -o 0.002

0.004

• 0.006

Radius (m)

77

. - - ,

0.008 0.01 0.012

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Figure 5-6. Hazardous Constituent Location Data used in the Analysis.

5

4.5 ---Co 4 a. 0 ex: 3.5 "5 .0

0 3 c 0 2.5 8

\ \

\ \ \

--(j) 2 0

J2 ~ 1.5 en 0 c 0 8

0.5

0 0 0.001 0.002 0.003 0.004 0.005 0.006 0.007 0.008 0.009 0.01

Radius (m)

From Table 5-1 size class 8 can be seen to be dominant. For this reason it was used as the reference size class in the simulation. The parameters used in the simulation for this size class are summarised in Table 5-2. The KP1 parameter corresponds to the chemical reaction rate being 10 times faster than the rate of fluid reagent diffusing into the reference particle.

Table 5-2. Reference size class parameters. (Reference Size Class = Size Class 8.)

B1 1.0 Kp,1 10.0 .llT 0.001

Figure 5-7 presents the profiles of fluid reagent A (solid curves) and one solid reactant (dashed curves) for each size class of panicle used in the simulation. Figure 5-8 shows the overall conversion of the system.

As expected, the smallest particles tend to react in a homogenous manner. These particles are sufficiently small for diffusion not to be rate limiting in any way. Instead, the release of hazardous constituents from these particles is dictated by kinetic considerations. As the particles get larger, they are seen to react in a more zone-wise manner.

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Figure 5-7 Con't. Fluid Reagent and Solid Reactant Profiles for the Smallest Size Class in the Simulation.

.. • " .. c • u c 0 u

• = c ~

I 0

o.e

o.6

0.4

0.2

············-·················-···········-···············

·····--···-····-··-··· ·····-················· ·-·-·································

····-············ ·················· ···········-·················-············ ·················· .......... . -··-· - . . . ................ ·····-· ............ ···-····-······-······ .. ··-···········-············

·····-···········································-·················-···········-······························-············ ·····--·-··-······ .......... --····· ...... ············-···········-···········-···················"'"'""""""-············ ....... ···········-···· .... ::::::::::::::::: .. :::::::::::::::::::::::: .. = : :·:::··:::::.·=.·.::.::·::: :::::::: ................... -·

0.0-l--~~~--l~~~~-+-~~~~1--~~~-+~~~---j o.o a.a o.q o.& o.s 1.0

DinensionJess Radius

Figure 5-8. Overall conversion for the System .

.1. 0

o.e

c 0 ... • I. • 0.6 ::> c 0

CJ

... • c 0 0.4 ... .. u • L. II.

0.2

O.O-t-~~~~~~-+-~~~~~~-+-~~~~~~-+-~~~~~~4--~~~~~---J

o.oo 0. J.O o.;;io 0.30 0.40 0.:50

DiMensionl-s React ion Ti~ <MAT Reference Particle:>

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Note that there is some numerical inaccuracy in the concentration profiles of the smallest size class shown in Figure 5-7. Although this inaccuracy can be eliminated by reducing the time step between iterations there is a· trade off between the time for computation and numerical accuracy. It is also important to note that the smallest particles will display the largest numerical inaccuracy. This can be seen from the fact that the smallest size classes have the largest relative time steps in the simulation (equation 5-12). Further, although the profiles in the smallest size class are inaccurate, they are unconditionally stable. This unconditional stability is a property of solving second order parabolic partial differential equations using the Crank-Nicolson method [Crank 1975]. Since the smallest size class in Table 5-1 contains such a low occurrence of particles, the numerical inaccuracy in this size class was deemed to be acceptable.

Figure 5-8 exhibits some interesting characteristics. The graph consists of two distinct sections: a straight line section accounting for the· fractional conversion at the beginning of the experiment, and a concave section later on in the experiment. The straight line section is characteristic of a kinetic controlled situation with an excess of fluid reactant. Effectively it represents the release of solid reactant from the small particles which react in a kinetic controlled manner. In contrast, the concave section is characteristic of a diffusion controlled reaction. Roman [1974] also observed these trends in conversion or recovery calculations. (Although Roman's calculations were for a column, a CSTR experiment can be considered as a very short column in which no mass transfer limitations are present.) ·

5.7.2 Effect of Particle Size Distribution on the Fractional Conversion.

The following scenarios, summarised in Table 5-3 and Figure 5-9, were used to investigate the effect of size distribution on the release of hazardous constituents. Note that all 51,k values were set to unity to eliminate their effect on the results. The parameters for the reference particle size wert? as previously defined in Table 5-2.

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Table 5-3. Summary of the conditions used to investigate the effect of Size Distribution on Fractional Conversion.

Particle Base Case Size Distrib. Size Distrib. fi(eJ Size. Size with with (mm) Distribution Predominantly Predominantly

Small. Particles. Large Particles.

9.5 0.252 1.0 1.0 1.0 8.5 0.428 1.0 9.0 1.0 7.8 1.045 1.0 55.0 1.0 6.5 2.564 2.0 9.0 1.0 5.8 6.191 2.0 5.·o 1.0 4.5 14.061 5.0 5.0 1.0 3.5 27.105 16.0 5.0 1.0 2.5 34.247 55.0 5.0 1.0 1.5 13.846 16.0 5.0 1.0 0.5 0.260 1.0 1.0 1.0

Figure 5-9. Summary of the Size Distributions used in the Simulations.

50

Q) 40 () c Q)

:; () ()

0

30 ............................ ..

'* 20

10 ...

··········-····················

~\····· ................................ ~ ...

o~t::-~-,-~~-r-~~=;:::~~~=-~*--~~--! 0 0.002 0.004 0.006 0.008 0.01 0.012

Radius (m)

- Base Case -+- Pred. ·Small Part. - Pred. Large Part.

Figure 5-10 presents the fractional conversion curves for these cases. The size distribution with predominantly smaller particles is similar to the base case size distribution. As such, the fractional conversion for the two cases is very comparable. As expected, the simulation using the size distribution with predominantly smaller particles predicts a higher conversion at all times compared to the base case simulation. Further, the linear, kinetic controlled region is larger for the simulation consisting of smaller particles. The fractional conversion is significantly delayed for the size distribution consisting of larger particles. In effect, the conversion is being delayed by diffusional

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resistances.

Figure 5-10. Fractional Conversion for the Size Distributions Investigated.

11odel:5E'.l Beta1 1.000; K-1 10.000; L-l. O.::SOO; GDT wr-'t ~l'Siz.Cl-• 0.0100 a.ta2 o.ooo; 1<--2 o.ooo; L.arll>d-2 o.ooo; u1...c1.... e

1.0

0.8

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0.0-+-~~~-+-~~~-+~~~~+-~~~-+-~~~-1

o.oo 0.10 o.ao o.3o o.40 o.:io

Di,_ionless Reaction Ti..., <MAT Aefer-ence Particle>

5. 7.3 Effect of the Location of Hazardous Constituents on the Fractional Conversion.

The following scenarios, summarised in Table 5-4 and Figure 5-11, were used to investigate the effect of contaminant location on contaminant release. The first case represents the physical situation in which no hazardous co'nstituents have been concentrated o_nto the surface of the particles. In other words these particles have a surface hazardous constituent concentration equal to their bulk concentration. The second and third cases represent the cases where the surface concentration of the smallest particle is 5 times and 10 times the bulk hazardous constituent concentration respectively. The r1,k values were determined as before, using equations similar to equation (5-19), and the parameters for the reference particle size were defined previously in Table 5-2.

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Table 5-4. Summary of the conditions used to investigate the effect of Hazardous Constituent Location on Fractional Conversion.

Particle Size. Size Case 1-r1,i. Case 2-r1 " Case 3-t1,i. ' (mm) Distribution.

9.5 0.252 1.0 1.21 1.47 8.5 0.428 1.0 1.24 1.53 7.5 - 1.045 1.0 1.27 1.60 6.5 2.564 1.0 1.31 1.69 5.5 6.191 1.0 1.36 1.82 4.5 14.061 1.0 1.44 2.00 3.5 27.105 1.0 1.57 2.29 2.5 34.247 1.0 1.80 2.80 1.5 13.846 1.0 2.33 4.00 0.5 0.260 1.0 5.00 10.00

Figure 5-11. Summary of the Hazardous Constituent Location Data used in the Simulations.

9 - --------- --- -------------

8 --

O+-~---,-~---,--, ~-,.-~---.~~.-~-.---~~,~~~. ~--,--~--1

0 0.001 0.002 0.003 0.004 0.005 0.006 0.007 0.008 0.009 0.01 Radius (m)

\ -+-- Case 1 . - Case 2. (Base) - Case 3.

Figure 5-12 shows the conversion curves for the different scenarios. As expected, the cases where hazardous constituents are concentrated onto the surface obtain higher fractional conversions for all times. This is caused by the fact that hazardous constituent deposits on the surface of the particles cannot be retarded by diffusional resistances (although they may be retarded by mass transfer resistances which have not been accounted for in this work). Also note that as the surface concentration increases, so too, the straight line kinetic controlled portion of the conversion graph increases.

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Figure 5-12. Fractional Conversion for Surface Hazardous Constituents Concentrations Investigated.

Hodel~l

e•t•J. i.ooo: K-..J. 10.000: L.-.J. o.:500: GOT wrt A9rs1z.c1-• 0.01.00 B<tt-2 0 .000; 1(-..2 0 .000; L.-.bcl-2 0 .000; Uf....Cl-• 9

c a .. • l.

1.0

o.e

~ 0.6 c a u .. ~ ,g 0.4 .. u • L. II.

0.2

0.0-1-~~~--t~~~~--~~~~1--~~~-t-~~~---1

o.oo O.l.O o.ao 0.30 0.40 O.:KJ

Di.-.sionles5 React ion T itoe <MAT Reference Particle>

5.8 Fittini: the Model to CSTR Results.

The complete CSTR model which predicts the fractional conversion as a function of dimensionless time for a size distribution of particles has many parameters. This is due to the fact that each size class of particles has the following parameters associated with it:

It is not possible to determine all these parameters simultaneously from a single CSTR experiment. Instead, a CSTR experiment which contains only a single size class of particles, termed the reference size class, must be used to determine the parameters for that size class. If the properties of the particles in the remaining size classes are sufficiently similar to the reference size class then the remaining parameters can be determined, through the relationships defined in equations (5-8) to (5-12). Alternatively when the particles in the other size classes exhibit sufficiently different properties to the reference size class, a CSTR experiment for each size class needs to be conducted to determine all the parameters.

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5.8.1 Model Requirements.

The following information needs to be known in order to fit the model parameters for a single size class of particles to CSTR results:

The relative stoichiometric consumption of the fluid reagent for each participating solid reactant;

the effective concentrations of the participating species;

the reaction orders with respect to the solid reactants;

the ratio C5/Cpi' (.\i,k), for each species in the reference size class; and;

the voidage of the particles.

Note that the discussion on model requirements presented in section 3.8.1 with respect to the chemical reactions, effective concentrations of the species and reaction orders is equally applicable to the CSTR model.

5.8.2 Fitted Parameters.

The fitted parameters in this model are the Kpi and Ksi groups. Notice that there is one Kpi and one Ksi group for every chemical reaction taking place. These groups are fitted by comparing the fractional conversion curves determined by the model to experimentally determined conversion curves.

Before the comparison between the model predictions and the experimental results can be made, the experimental results need to be converted into appropriate dimensionless form. Typical experimental results will be in the form of curves which represent the dissolved concentration of the hazardous constituents in the bulk fluid as a function of time. These curves can be converted into fractional conversion versus time curves. This is a straight forward procedure because the total leachable concentration of each species is known. (The total leachable concentrations of each species can be obtained by conducting a leach test until no further hazardous constituents are released. The bulk fluid concentrations can then be used ·to back calculate the leachable concentrations within the waste particles.) Non­dimensionalising the time variable is a more complicated procedure. It is usually not feasible to use the dimensionless diffusion time, 't, defined in equation ( 4-15), to non-dimensionalise the time. The reason for this is that the dimensionless diffusion time includes the effective diffusivity for the particle which is unknown. The dimensionless group defined as:

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k -Ccl>Ri C 'K .A ·'t= pi pi,O A,O t

piPi C. EJ.,0

( 5-21)

and which is termed the dimensionless reaction time can be used to non-dimensionalise the time variable. The reason for this is that the total extractable grade, Cei,O , and the group kpiCpi<\Jsi CA,o , which represents the initial reaction rate, are known. (The initial reaction rate can be determined from the initial slope on the experimental concentration versus time graph). Thus the dimensionless reaction time, equation (5-21) can be used to non­dimensionalise the time variable to yield a totally dimensionless experimental curve. By coding the model to predict the conversion versus dimensionless reaction time curves, the model predictions can be compared to the experimental results.

Note that if the hazardous constituents on the surface of the particle can be assumed to react in the same manner as the hazardous constituents within the particle then only the Kpi groups are fitted to the experimental results.

5.9 Applications and Limitations of the Model.

5.9.1 Applications of the model.

As the name implies, the CSTR model is particularly suited to the analysis of CSTR experimental data. Once parameters for a reference size class have been determined, the effects of the following factors on the release of hazardous constituents can be investigated:

particle size distribution;

hazardous constituent concentration;

hazardous constituent location; and;

competing reactions.

The CSTR model is also used to determine the model parameters for the Columnar Model presented in the next chapter.

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5.9.2 Limitations of the model.

The CSTR model has two main limitations. Firstly it cannot be used in cases where there are significant mass transfer resistances because these have not been accounted for in the model. Should the functional relationship between the bulk fluid reactant and the surface fluid reactant concentration be known, it would be easy to incorporate the mass transfer resistances into the model. The second limitation is that the model cannot be

applied to a case where the diffusion of the dissolved solid species is rate limiting. Dixon [1993] has included this aspect into his previous model [1992]. The inclusion of dissolved species transport limitations into the model are discussed in section 7.

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Chapter 6. A Microscopic, Columnar Model to Describe Leachate Generation and Mobility in Granular Waste Deposits.

The macroscopic, lumped parameter model, which was described in Chapter 3, essentially modelled a waste deposit as a single columnar entity. No particulate features within the column were identified in this model. Instead, the contributions of the effective chemical reaction rates, hazardous constituent location and hydrodynamic aspects where lumped together in a parameter which described the effective rate of release of hazardous constituents from the column.

As previously discussed, the main limitations of this model result from using this lumped parameter approach. The most notable limitation is that the individual contributions of the effective chemical reaction rates, hazardous constituent location or hydrodynamic aspects on contaminant release cannot be determined. The overall effective chemical reaction rate for the column is a function of the size distribution of the particles within the column since different sized particles react at different rates. Hazardous constituent location within the individual particles also plays an important role in the release of these constituents. This too in known to be a function of particle size and has been discussed in section 2.1. l. The hydrodynamic aspects, previously discussed in section 2.1.2,are affected by the superficial velocity of the fluid entering the column and by the size distribution and packing of the particles within the column. Since these factors are all dependent on particulate features, a more detailed model which includes particulate information has been investigated.

The heterogenous, columnar model is essentially a columnar, non-catalytic, packed bed reactor type model. The main difference between it and the macroscopic, lumped parameter model is that the particles within the column are included in the model description. Figure 6-1 graphically shows the differences between the two models.

Figure 6-1 Graphical comparison between the macroscopic, lumped parameter model and the heterogenous, columnar model.

No internal structure is considered in

~ the Macro­scopic, Lum pee Parameter Model.

89

Lysimeter and internal packing considered in Heterogenous,

__. Columnar Model.

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Two methods to determine an appropriate solution strategy for the heterogenous, columnar model are presented. The first and more simple method is based on the heap leaching modelling strategy of Roman et al. [1974] .. The second method, which is a more rigorous mathematical approach, results in a solution strategy identical to Roman's strategy and has been included merely as a validation of the simpler approach.

This presentation is followed by a section which indicates how a global wetting factor has been incorporated into the solution strategy. Next, the details of suitable computer routines which have been written to implement the solution strategy are discussed. The model has been verified against experimental results which have been presented in a paper by Roman et al. [1974]. The last section in this chapter summarises the experimental data which is required in order to verify the applicability of the heterogenous columnar model to describe the leaching of hazardous constituents from waste deposits.

The following chapter summarises the application of the heterogenous, columnar model to predict the release of hazardous constituents from waste deposits. This chapter also includes a discussion on the advantages of the heterogenous, columnar model over existing models as well as giving details with respect to possible extensions to the model.

6.1 A Modelling Strategy based on Heap Leaching Models.

The strategy adopted in heap leaching models has already been discussed in section 2.4. In summary, the general strategy is to conceptually divide the heap into columnar sections. Each column is then further sub-divided into a series of disks within which the fluid concentration is assumed to be spatially uniform. It is important to note that if the column is divided into too few disks, the assumption that the fluid reagent concentration within each disk being spatially uniform will no longer be valid. The accuracy of the assumption with respect to uniform spatial fluid concentration will increase as the number of disks within the column increase. These sub-divisions of the deposit and columnar sections were shown in Figure 2-5.

The flow of fluid through the column is simulated by allowing the fluid from one disc to replace the fluid in the disk below it at specified time intervals. During each time interval, the fluid reactant is allowed to react with the solid particles resulting in the precious metals, or hazardous constituents, being released.

It is important to note that, within each time interval, each disk in the column consists of an assembly of particles associated with a finite volume of fluid reagent. Since film mass transfer effects have been assumed to be negligible, the decrease in the fluid reagent concentration within each disk and time interval can be described by the CSTR model which was developed in the previous chapter even although the physical characteristics of a CSTR are very different from that of a 'reactor slice' or disk. Since each disk is being described by a CSTR model, the behaviour of the column is being approximated by a number of tanks in series. (The number of tanks corresponds to the

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number of disks in the column.)

The modelling strategy has been summarised in Figure 6-2.

Figure 6-2. Summary of the Solution Strategy used which was based on Roman's Solution Strategy.

j For each time interval:

'\ J,

•Allow the fluid from each disk to replace the fluid in the disk below it. The fluid in the first disk will need to be supplied from a reservoir and the concentration of this fluid forms the boundary condition for the column. The fluid from the bottom disk is discharged from the column and represents the breakthrough fluid.

•Apply the CSTR model to each disk. (Note that the CSTR model can be used because mass transfer resistances from the bulk fluid phase to the liquid/solid interface have been assumed to be negligible.)

Iterate in time.

The equations which describe the release of hazardous constituents within each disk during each time interval, which constitute the CSTR model, have been presented in the preceding chapter.

Effectively the time intervals which elapse between successive fluid replacements represent the time which the fluid would have taken to flow through the disk. Thus for a constant volumetric flowrate, q, the time intervals can be determined from:

where €c01

Col% Sat

A~coI

At= Fluid Volume of Disc q

EcolCOlrg Sat A~col L A

q

column voidage;

(6 -1)

saturation . of the void space within the column; dimensionless length of a disk;

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L A

length of the column; and; area of column.

For a volumetric flowrate which is a function of time, At will need to be determined from (tn+ 1-t1) where (tn+ 1-tJ is obtained from:

Cn+l

J q( t) dt=ecol Col, sac A~col LA (6 -2)

t;n

Since the computer routines which' have been written for the CSTR model are in dimensionless format, it would be convenient to express the time intervals between successive fluid replacements in dimensionless form. These time intervals can be converted to non-dimensional quantities by dividing them by a reference time period. One appropriate reference time period is the space time of the column defined by equation (3-13):

L T=­·u •

( 6 -3)

where u· is a reference fluid velocity (percolation velocity) which has arbitrarily been set at lm per 24 hours.

6.2 A Modellini: Strate2y based on a Rii:orous Mathematical Approach.

The starting pQint for this analysis is a mass balance equation which describes the bulk fluid reactant concentration within the column. To obtain this equation an approach very similar to the one adopted in the macroscopic model development can be used. The only difference is that the rate term, rai' which represents the 'production' of fluid reagent due to chemical reaction, is retained in equation (3-5) and not replaced by an overall lumped rate expression such as equation· (3-2). The modified form of equation (3-5) is:

acA acA n E Col col =-u col+~ I

Col % Sat: a LI t az i=l ai ( 6 -4)

The same equation expressed in dimensionless terms is:

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acxcol =-DGl acxcol +----L ____ £I

a I ai: *C C 1 ' A1 't "col U Ao Ecol 0 % Sat .i=l

(6-5)

where DGl is as previously defined in equation (3-14), and has the physical significance of being the ratio of the fluid ·percolation velocity to the reference fluid percolation velocity.

The appropriate initial and boundary conditions for this equation are:

«col (~Col' 0) =O (6-6)

( 6 -8)

Equation (6-5) is a first order hyperbolic partial differential equation. As discussed in Chapter 3, the method of characteristics can be used to convert the partial differential equation into two ordinary differential equations. These equations are:

( 6-9)

and

dabulk L I:ri

d't' CA bulk0 Ecol Col% Sat U *

(6-10)

It is interesting to note that the term on the right hand side of equation ( 6-10) represents a normalised - rate of consumption of fluid reactant over the rate of fluid reactant replenishment. In this regard, this term represents the same ratio as the previously defined dimensionless group DG2.

Before these equations can be solved, suitable expressions for the rate of 'production' of fluid reactant A by the i reactions, rAi, need to be determined.

Rather than redevelop these expressions, recall equation (5-16):

~ [ VPazt kPa ( 1-Eo) ~ dCs1 n I 3 VPazt k] dCA .,. · .,. -D vC • -v k b . -dt e A Rk R - Liq. dt

=1 i i=l k . ( 5-16)

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where V Part,k is the total volume of particles in size class k; M number of sizes classes; and; Rk Radius of the particles in size class k.

This equation expressed in dimensionless format is:

~ r-f iPaxt,k a4>s:1 N - 3iPaxt,k ( aa;) I ] = VLiq Ksi,k si,k "'bulk 2 ~~ k ~=l

k=l i=l 0 k2 ak u.., e v o or o Part.

(5-17 or 6-11)

This equation describes the change in the bulk fluid reactant concentration as a result of the fluid reactant being consumed by chemical reactions within a range of different sized particles. Note that the time variable used in equation (6-11) corresponds to a dimensionless diffusion time corresponding to the reference size class of particles. In contrast, the time variable used in equation (6-10) corresponds to a dimensionless space time of the column. If the column time increment is set equal to the reference size class time increment then equation (6-11) can be used in place of equation (6-10). This implies:

where Eo

VPart.

Vu q.

TPart,k

panicle porosity;

da; bulk da; bulk

en - d-r.'

(6-12)

in this case represents the total volume of the reference size class particles within the spatial increment in the column; in this case represents the volume of fluid within the spatial increment in the column; defined in equation (5-18) ·and which represents the ratio of the Yolume of the particles in size class k to the volume of the particles in the reference size class; and; defined in equation (5-5) and which represents the ratio of the average radius of the particles in size class k to the average radius of the particles in the reference size class.

The overall mathematical solution strategy can be summarised as follows. Firstly set a suitable spatial increment, A~c01 , for the column. This increment corresponds to the length of a disk in the previous heap leaching analysis. Equation (6-9) is then used ·to

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determine the time increment for the column. As shown in Chapter 3, an alternative method to determine the time increment for the column is:

(3-31 or. 6-13)

where (tn+ 1-tJ is obtained from:

tn+l

J u ( t) dt = Ecol Col, Sat t:.Z

=ecol Col, sat A~col L (3-32 or 6-14)

Notice the similarity between equation (6-14) and equation (6-2). In effect these two equations are identical.

Within each time increment and within each spatial increment the change in the bulk fluid reactant concentration can be solved using equation (6-12). Before this equation can be solved however, the fluid reagent profiles within each particle size class need to be known. These can be determined by applying the particle scale model of Dixon to each size class of particles. This approach is summarised in section 5.4.

It is important to note that in reality it is not always feasible to set the column scale time increment equal to the particle scale time increment. The reason for this is that the column time increment is usually sufficiently large to result in the Crank-Nicolson method, used to solve the particle scale concentration profiles, becoming totally inaccurate. This problem is easily overcome by using a much smaller time increment for the particle scale calculations and repeating these calculations until the cumulative time increment for these calculations is equal to the column scale time increment. This can be summarised as:

n A'tParticle scale=A'tcolumn Scale (6-15)

where n is the number of times that the particle scale calculations need to be repeated.

The solution strategy has been summarised in Figure 6-3.

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Figure 6-3. Solution strategy derived from a rigorous mathematical analysis.

Choose an appropriate column increment, Ll~c01 ;

Use equation (6-9) to determine an appropriate time increment, Llr';

Within each time increment do:

•Within each spatial increment use equation (6-12) to determine the fluid reagent concentration. (This effectively involves solving a set of equations identical to the CSTR model equations defined in section 5 .4.)

Iterate in time.

Comparison of Figures (6-2) and (6-3) shows that the solution strategy derived from the rig~rous mathematical analysis is identical to the simpler heap leaching modelling strategy.

6.3 Inclusion of a Global Wetting Factor into the Solution Strategy.

A global wetting factor has been incorporated into the solution strategy to account for the partial wetting of particles. The global wetting factor represents an average fraction of particle surface area wetted by fluid reagent. As an example, a global wetting factor of 0.5 implies that all of the particles are only half covered by fluid reagent. It has further been assumed that sectors within particles which are bordered by dry external surfaces will not release hazardous constituents. In effect, this implies that even with dry zones within a particle, the diffusion will remain one dimensional - in the radial direction only.

From the above discussion, wetting can be seen to influence the release of hazardous constituents in the following manner. Firstly, the degree of wetting determines the solid which is available to react with the fluid reagent. As before, a global wetting factor of 0.5 implies that only half of the particle volume is available to react with the fluid reagent. This in effect also determines the maximum release of hazardous constituents _achievable. A column with a wetting factor of 0.5 will have a maximum contaminant release (conversion) of 50%.

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Using this information the effect of partial wetting was incorporated into the solution strategy as follows. Equation (6-12) has previously been used to determine the bulk fluid reagent concentration within the particles as a function of time for totally wetted particles. This equation can still be used in the case of partially wetted particles if V Part.,k

is defined as the product of the volume of the particles in size class k within a spatial increment within the column and the global wetting factor. This can be summarised as:

v = y v Part, k Part, kActual ( 6 -16)

where V Part,k,ActuaI in this case represents the actual volume of the particles in size class k within the spatial increment in the column;

V Part,k in this case represents the volume of the particles in size class k which is available to react with the fluid reagent within the spatial increment in the column; and; is a global wetting factor.

By using a global wetting factor, all particles have been assumed portion of their external surface area covered by fluid reagent. information with respect to particle wetting as a function of particle could be included into the model as follows:

v = y v Part, k k Pazt, kActual (6-17)

where 'Yk is a size dependent wetting factor.

to have an equal If more detailed

size is available, it

6.4 Suitable Computer Routines for the Heteroi:enous Columnar Model.

Program Model6Cl.PAS and Model6C2.PAS are suitable computer codes for the heterogenous, columnar model. As before, Model6Cl.PAS is a code which assumes a solid reaction order of unity while Model6C2.PAS can accommodate a variable reaction order.

These codes are sufficiently large to justify some explanation as to their organisation. From the discussion on the solution strategy in the previous section it became evident that the codes need to calculate, as a function of time, the reactant profiles within each particle size class within each disk of the column. This information is then related to the fluid reactant and dissolved hazardous constituent profiles within the column itself.

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The particle scale calculations, which are essentially identical to the CSTR model calculations are incorporated in Unit6Cl and Unit6C2. These units are almost identical to previous PASCAL codes Model5El and Model5E2 respectively. All the particle scale parameters are defined and set in these units. The column scale calculations are performed in the main program Model6C 1 or Model6C2. All the column parameters are defined and set in these programs. Figure 6-4 summarises the overall organisation of program Model6Cl.PAS.

The output of these codes is a display of the solid and fluid reactant concentration profiles for the smallest, largest and reference size class of particles as a function of time and position within the column. This information helps to visualise how the different size classes are reacting in different positions of the column at different times. This inf9rmation is most useful because it helps to identify which size classes of particles react in a chemical kinetic controlled manner and which react in a diffusion controlled manner. In effect, this information can be used to determine the relative importance of intrinsic chemical kinetics and diffusive resistances on the overall rate of release of hazardous constituents. A typical display of the solid and fluid reactant concentration profiles is shown in Figure 6-5.

Once the required iterations in time have been performed and the calculations are completed the programs display the conversion and breakthrough curves as a function of dimensionless time. Although the computer routines do not presently display the concentration profiles within the column as a function of time, the data required for these curves is already calculated. Thus this feature can easily be incorporated into the computer routines if required.

Figure 6-4. Summary of the overall organisation of Program Model6Cl.PAS.

Model6C.

Column Scale Calculations.

The main program contains all UoitflQ, the column parameters. Particle Scale

Calls Unit6C Calculations. ... ... to perform ... . particle ' This unit contains

scale calculations. all the particle parameters.

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Figure 6-5. A typical display produced by Model6Cl.PAS showing the solid and fluid reagent profiles for the smallest, largest and reference size class of particles.

BetaJ. Beta2

t,I c 0

LJ

Ill Ill ... :i: Q

LI ,. i3 CJ

~ 11 .. c

i:::

Uni tGC.1 i.ooo; KaDDaJ. 10.000; La,.,baaJ. o.ooo; oraerJ. i.oo; GOT o.ooo:5

·oo; KaP?a2 o .ooo; La ... bda.2 o .ooo; oraer2 i .oo

L • 0 l.~~=~.'.~.~ ....... ~ ... ~~~.~ .......... ~=~~.' .. '.~~ ... ~~:::=~~·~·;;;i~;~.;'.:::.., B

a.a.

0.6

0.4

a.a

DiMensionless Radius

SMallast Siza Fraction L~r-a-st Siz• Fraction

0.2 0.4 J.. 0

Di~ionless Radius DiMenSionless Radius

It is worth p.omtmg out that these programs include numerical step size scaling procedures. As such, the programs have been written to detect numerical stability and to increase the step size used in the calculation strategy whenever appropriate. The main advantage of using such procedures is that the overall calculation time can be greatly reduced.

Copies of the code as well as solution algorithms can be found in Appendix V.

6.5 Verification of the Computer Routines.

Roman et al. (1974] conducted two lysimeter tests which were significantly different in terms of lysimeter dimensions, fluid reagent concentrations and flow rates, and the size distributions of particles, in order to determine the predictive capability of their model.

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In summary, they used one set of data to determine the single unknown parameter in their model and then used the model to predict the second set of data. Although the heterogenous, columnar model presented in this chapter is capable of incorporating far more complexities than the model presented by Roman et al. [1974], its predictive capacity can be tested in a similar manner.

The lysimeter experiments conducted by Roman were concerned with copper extraction. The physical properties, operating conditions and size distributions of the particles used in the two experiments have been reproduced from Roman [1974] and are summarised in Table 6-1 and 6-2, and in Figure 6-6 and 6-7 .

Roman et al. did not include the voidage of the ore particles in their data and this value has been assumed to be 1 % . It is important to note that the Kpi parameter used in the heterogenous columnar model is the ratio of the chemical reaction rate within a particle to the effective rate of diffusion of fluid reagent into the particle. The effective rate of diffusion of fluid reagent into the particle is a function of the particle voidage. The effect of particle voidage on the effective diffusivity has not been considered in the heterogenous columnar model. The particle voidage only affects the heterogenous columnar model through the continuity equation ( 4-1). Equation ( 4-6) is equation ( 4-1) in expanded form. The heterogenous columnar model was determined to be relatively insensitive to small changes in particle voidages in the region of 1 % . For this reason a particle voidage of 1 % has been assumed to be an adequate assumption.

The acid consumption which was determ~ned experimentally has been assumed to include the effects of fluid reagent holdup within the particles. This implies:

Acid Consumption=~e- b l-E copper (6-18)

where bcopper is the mass of copper released per mass acid consumed.

Table 6-1. Physical Properties and Operating Conditions.

Lysimeter 1. Lysimeter 2.

Weight of ore. (kg) 121 74.5 Column height. (cm) 176 305 Column diameter. (cm) 25.4 14.3 Solution flowrate. (l per min per m2) 0.155 0.652 Acid concentration. (gpl) 48.8 69.7 % Voidage. 49.8 42.3 % Saturation. 36.1 37.1 Acid consumption. (g Acid per g Cu.) 3.6 3.6 Copper grade. ( % ) 1.9 1.9 Ore specific gravity. 2.7 2.7

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Table 6-2. Size Distributions. (% Occurrence.)

Particle Size. (mm) Lysimeter 1. Lysimeter 2.

37.5 58.1 -37.5 - 25.0 15.8 -25.0 - 19.0 10.3 -19.0 - 13.2 4.1 29.8 13.2 - 9.5 3.2 22.9 9.5 - 6.7 1.8 15.0 6.7 - 4.75 1.3 6.4 4.75 - 3.35 1.0 5.4 3.35 - 2.36 0.6 3.3 2.36- 1.70 0.5 1.9 1.70- 1.00 0.5 1.9 1.00 - 0.85 0.3 1.6 0.85 - 0.60 0.3 1.6 0.60- 0.425 0.3 1.4

- 0.425 1.9 8.8

The size class used as the reference size class in both simulations was arbitrarily chosen as the 9.5mm to 13.2mm size class.

Since no appreciable amount of copper is concentrated on the surface of the particles the 'surface grade'' csi 0• was assumed to be zero for all particles.

Using this data, the only unknown parameter in the simulation is the Kcopper parameter which represents the ratio of the intrinsic chemical reaction rate within the reference size class of particles to the rate of fluid reagent diffusing into these particles. Using the experimental data for the second lysimeter, this parameter was determined to be 4.5 for the reference size class (9.5mm to 13.2mm). It is worth noting that the model is fairly sensitive to this parameter. For example, running the model with Kcopper=4 and Kcopper=5 resulted in significantly different curves to the experimentally determined curve. Further, the model converges to a Kcopper value of 4.5 irrespective of the whether the initial guess for the Kcopper is larger or smaller than 4. 5.

Using a value of 4.5 for the Kcopper parameter, the model was used to predict the performance of the first lysimeter. The results of both simulations compared to the experimental points are shown in Figure 6-8.

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Figure 6-6. Size distribution of the particles in Lysimeter 1.

60,--~~~~~~~~~~~~~~~~~~~~~~~----,

i I i I

.....• ······························1 50 ······················································································································· ··································

I I 40 ······································································ ···················································································· : ................... 1

§ I I ~ i I g 30 ·-.. ···························································································································----·····:··············· .. ·······························-r-·····---·························I

o I * 20 ................................................................................ : ........................................................... ·····!················· ··1

' / II

10+··········:··············································································································--······································,~-·: ....................................... 1

0+1~~~~:::::;:::::;:~··· ~,·~~.~~.=-•1::=••,:::::::m~~,~~~~~~~1-1

~.,.---,--,--,-..,.1~1_,_j,] 0.1 1 10 100

Average Particle Size (mm)

Figure 6-7. Size distribution of the particles in Lysimeter 2.

50 .................................................................................................................. ·--···-·-·····················································································

~ 40-1 ------·································-··· -----······-················ ···········-·-························1

j 30 i········ --··································· -··························· - -···-··-····-··· 7-····· ·························· -····i

* • 20 ..................................................................... ~---·-···········-·····················--·-····-1- - -- - - -1

I . 1 0 ....... ······· ····ii(······· ........ ················ .................................... ······················-!-············ .. ·········

I ·"--, I '--,

i ~--~=~----------~ 07,~~-r----:---:---;-r.,-.,.....,-:-~~-,--,-~~-..,.-,~ ,,,~~~~~~~-.~.

0.1 10 100 Average Particle Size (mm)

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Figure 6-8. Fitted curve and predicted curve for Model6Cl compared to the experimental points of Roman [1974].

0.9 ······················-·····. ·························································· ........................ ············································ ········ ....... ··········

c 0.8 ..................... ' -··················································---·····-····--··············--···················--···················---···············--····----·---·-·-········--······

i ~:: :::~:- _:J;.~::: : mm mm ::: ::mmm-m•••~::::::·:::::::::::::::: ::-j 0 0 ->.. '-

~ 0.4 0 g 0.3 a: cfl. 0.2

0.1 ................................................................................................................ \

O-='--~-,~~~~~~~~~~~~~~~~~~~~~~I 0 5 10 15 20 25 30 35 40

Time (Days)

\ --- Experimental Points -e- Model; Kappa=4.5

Figure 6-8 shows that Model6Cl is capable of accurately predicting the performance of heap leaching experiments.

6.6 Determination of the Heteroaenous Columnar Model Parameters from Appropriate CSTR type Experiments.

In the previous section, the parameters for the heterogenous, columnar model were determined from a lysimeter experiment. Where external mass transfer resistances are negligible, the model parameters can be determined from an appropriate CSTR type experiment.

The model parameters would be determined as follows. A CSTR experiment would be conducted on a single size class of particles which would then represent the reference size class of particles. The CSTR model would then be fitted to the experimental curve as discussed in section 5.8. These parameters could then be used as the reference size class parameters in the heterogenous columnar model.

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This strategy will be demonstrated in reverse. The model parameters in section 6.5 were determined from fitting the heterogenous columnar model to a lysimeter result. Using the parameters determined, the predicted CSTR conversion versus time curve corresponding to 0.1/ of 9.5mm to 13.2mm particles and 1/ of 48.8 gp/ of acid is shown in Figure 6-9. This curve was predicted using the CSTR model presented in the previous chapter. The significance of Figure 6-9 is that it is the conversion versus dimensionless concentration curve which would have been obtained had a CSTR type leach test been used instead of a lysimeter test. This demonstrates that parameters determined from one type of experiment can be used to predict the performance of other CSTR or lysimeter scenarios.

Figure 6-9. Predicted CSTR conversion versus time curve for O. llof 9.5mm to 13.2mm particles and 1/ of 48.8 gp/ of acid.

S.t•J. 0.26-4; Kat>Q•J. 4.~; L•Ml><l•J. o.ooo; GOT ..,rt Rer-s1z.c1 ... o.~oo

S.t-2 o.ooo: KMX>-2 o.ooo: L...VXS-2 o.ooo; V!.....Cl••• :s

c: c -• I.

1.0

O.B

~ 0.6 c: c (J

0.0 :d.O 4.0 6.0 8.0

OiMen5ionJ~s React ion T i.-.e <MAT Reference Part icJe)

10.0

There are distinct advantages in using a CSTR type experiment to determine suitable model parameters for the heterogenous columnar model. Probably the most important advantage is the short duration of a CSTR experiment. Most heap leaching type models make use of lysimeter data in order to determine the model parameters. (This is exactly the procedure used in the previous section to verify the model.) As previously stated, lysimeter tests typically last for at least a few months and can last up to 3 years. In contrast, a CSTR type leach test takes at most a few days to complete. This means that the potential release of hazardous constituents from a proposed deposit can be determined much more quickly than before. This is a significant advantage in that the mineral processing industry needs to know the likely impacts of certain disposal strategies so that it can determine wether or not the present disposal strategies are adequate. Before, the industry would merely dispose of the wastes and conduct a lysimeter experiment to determine the likely impacts of the disposal strategies. This information would then be used to improve future disposal strategies. In cases where a disposal option was determined to pose a significant risk to the environment, the industry was faced with the expensive rehabilitation or reprocessing of the waste material. The ability

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to predict the likely impacts of the disposal strategies· a priori will help to eliminate the costly rehabilitation or reprocessing procedures.

The financial savings incurred by conducting CSTR type experiments over lysimeter experiments are also significant. CSTR experiments are much cheaper to conduct than lysimeter experiments. This has significance in that existing deposits can be investigated to determine their environmental risks. Previously, suitable lysimeter experiments for all waste deposits were not feasible due to the costs associated with these tests. By making use of the cheaper CSTR tests, samples from these deposits can now be tested to determine their potential to pollute the environment.

6.7 A Summary ofthe Experimental Data which is Required to Verifythe Applicability of the Hetero2enous Columnar Model to describe the Leachin2 of Hazardous Constituents from Waste Deposits.

In order to demonstrate the applicability of the heterogenous columnar model to describe the leaching of hazardous constituents from waste deposits, it. needs to be verified against suitable experimental data. Section 6.5 verified that the computer routines were operating correctly by testing them against heap leaching data for copper. Although this shows that the model can be used to accurately predict the leaching of copper from a heap leaching operation, the ability to predict contaminant leaching from a waste deposit still needs to be demonstrated.

This project has not involved any experimental work. Where experimental data has been required, data which has been reported in the open literature has been used. Unfortunately, suitable data is not reported in the literature which can be used to verify the applicability of the heterogenous columnar model to contaminant leaching from waste deposits. This section summarises the type of data which is required and suitable methods to verify the model using this data.

It may be· worth pointing out some of the short comings of data reported in the open literature so that these can be avoided when suitable experiments are planned and conducted. Firstly, although there is data on leach experiments for waste particles, these leach experiments have always involved a size distribution of particles. The reason for this practice is probably due to the fact that leach tests have been typically used to determine the 'leaching potential' of wastes. To determine this 'leaching potential', a sample of the waste, which inherently involves a size distribution of particles, is leached and the final leachate concentration is taken as a measure of the 'leaching potential'. These tests are usually termed Toxicity Characteristics Leaching Procedure tests (TCLP tests) [US Government Printing Office; 1988, 1980]. These experiments have not been used to model the effective release of hazardous constituents from waste particles. It has been continuously demonstrated in this thesis that the leaching of hazardous constituents from waste particles is dependant on the particle size. Thus to determine the effective

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release of hazardous constituents from waste particles a leach test on o single size class of particles is required.

0

The second factor is that the heterogenous columnar model describes the leaching of hazardous components from wastes. Some hazardous components of wastes are released due to dissolution reactions. It is unlikely that the chemical reaction model used in the heterogenous columnar model can be used model dissolution reactions. The reason for this is due to the fact that dissolution reactions are controlled by solubility constraints which have not been included into the model. Instead the model describes the rate of hazardous constituent release by making use of a kinetic expression corresponding to equation (4-2). Thus care should be taken not to apply the model to instances in which hazardous constituent dissolution is significant.

It goes without saying that a model can only be applied to situations for which it was designed. With this in mind, the heterogenous columnar model has been designed to describe the active leaching of hazardous components from granular waste deposits in which there is no external mass transport resistances. (The external mass transport resistances refer to the transport of components from the bulk fluid phase to the fluid/solid interface and vice versa.) Additionally, the particle characteristics as a function of size have been assumed to be fairly uniform. The only exception to this is that the concentration of hazardous constituents on the surfaces of the particles, and thus the total leachable concentration of hazardous constituents, has been allowed to vary as a function of particle size.

There are two stages to verifying the ability of the heterogenous columnar model to describe the leaching of hazardous constituents from waste deposits. The first stage involves determining whether the model can be fitted to lysimeter data and then used to predict other lysimeter operating conditions. This approach is very similar to the strategy adopted by Roman et al. [1974] and used in section 6.5. This approach would involve setting up two different lysimeter experiments. These experiments could differ in terms of the column heights used, the fluid flow rates through the columns (which in turn would affect column saturation and the wetting efficiency), the fluid reagent concentrations and the particle size distributions. The results of one of the columns could be used to determine the parameters in the heterogenous columnar model. The -model could then be used to predict the results of the second column and the predictions compared to the actual results.

The second stage involves determining whether the heterogenous columnar model parameters could be determined from a suitable CSTR experiment. This would involve conducting a CSTR experiment on a single size class of the waste particles and determining the model parameters as described in section 5. 8. These parameters would then be used in the heterogenous columnar model to predict the two column experiments discussed above. Once the model has been verified in this manner it could be used with confidence to predict the leaching behaviour of hazardous waste constituents from waste.

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An initial investigation into determining the particle-scale model parameters from a CSTR type experiment on a single size class of waste particles has been conducted. The data used in this analysis is from an experimental program currently being conducted at the University of Cape Town. The experimental conditions are summarised in Table 6-3.

Table 6-3. Summary of the Conditions in the CSTR Test on a Waste Sample.

Waste type. Stainless steel electric arc furnace dust.

Volume of fluid reagent. 1.6 l

Mass of waste particles. 0.04 kg

Particle Voidage. 1 %

Solid density. 2900 kg/m3

Average particle size. 3e-6 m

The pH remained fairly constant at a value of 10 during the experiment.

The concentration of dissolved magnesium in the bulk fluid was used as a measure of the leach potential. This is shown as a function of time from one CSTR experiment m Figure 6-10.

Figure 6-10. Concentration of Dissolved Magnesium in the Bulk Fluid as a Function of Time.

-E a. a. -c 0 -ca ,_ -c <Ll (.) c 0 u 0)

2

1a~~~~~~~~~~~~~~~~~~~~~~~~-,I

16 ·····························/·~¥·· I

14

12

10

8

6

4

2

I I

0... I

················±-·/···················· f, • . ·····················-r·············

• I

I .................. '-.. .... ,, .................. .

I I ,

I ............ , .. ··················· ··············································································································

I I ,

·I .......... .!

o~,L-~~~~~~~~~~-.--~~---,~~~--.-,~~~---r-~~----j

0 100 200 300 400 500 600 700 Time (min)

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The point labelled (a) in the diagram has been taken to be an outlier. The curve drawn through the experimental points is the expected increase in the magnesium concentration in the bulk fluid with time based on the data points. This curve was used to back calculate the total extractable grade, CEio' of the magnesium.

These initial reaction rate for the release of the magnesium has been determined using the initial increase in the bulk fluid concentration of magnesium as follows:

( 6 -19)

is the dissolved fluid phase concentration of solid reactant i; is the volume of the fluid in the batch test; and; is the mass of the waste particles in the batch test.

The total extractable grade and the initial reaction rate were used to prepare the fractional conversion versus dimensionless reaction curve as described in section (5-8). This curve is shown in Figure 6-11.

Figure 6-11. Fractional Conversion versus Dimensionless Reaction Time.

1.....-~~~~~~~~~~~~~~~~~~~~~~~--,

0.9

0.8 ··············································· .... c Cl. ·§ 0.7 ···················+·····································

Q) • • > 0.6 c 0 0 0.5

························································· .::::::::.:::.:·.:::::::::·.::.::.:.::::::::·.:::::J

I m c 0 0.4

:;:::; (.)

························ ··················································································································································· ···········································1

m ..... LL

0.3

0.2

0.1 : : : : : :~ : : : : : I

0-""--~~~~~..---~----,~~---.,-,~~-,.-,~~--.-~~-,-~~-.--~------1

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 Dimensionless Reaction Time

Mode15El was fitted to Figure 6-11 and the results are shown in Figure 6-12. The dashed curve in this figure corresponds to the curve in Figure 6-11. The solid curve is the fractional conversion calculated using Mode15El. The parameters fitted in the model

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were B, which represents the dimensionless reagent strength relative to the concentration of the magnesium in the waste; Kpi - Damkohler II number for the magnesium within the waste particles; and; ~which is the ratio of the surface grade of magnesium to the bulk grade of magnesium. The magnesium on the surface of the particles has also been assumed to react in a similar manner to the magnesium in the bulk of the particle. This is the reason why there is no explicit dependence on the surface kinetics in equation (6-19). The values determined by an initial fit are summarised is Table 6-4. There is excellent agreement between Model5El and the CSTR data from a sample of metallurgical waste.

Table 6-4. Values of the Fitted Parameters.

B1 0.8

Koi 30

~ 1.0

Figure 6-12. Model5El versus CSTR Experimental Data on a Waste Sample.

Hodel:5E1. Betai o.eoo; Ka!X)a1 40.000; Lal'\bda1 o.~oo;· GOT Yrt Ae~SizeClass 0.0020 Beta2 o.ooo; Ka!X)a2 o.ooo; LaMbda2 o.ooo; UteYClass 1.

.1. a

a.a

c: 0.. ,, -0 .. , . ._~~"~ ... ,,. UI , I. • • / II a.6 :> L Oo\\tci CUfUC co<~cb c: 0 ' CJ v lo cu.Na \4\ ':f"~\UI!. c.-1t. ... 19 c: 0 a.4 ... ..

te:s~lh ~ 'ic:de16EI. u

5.ltd CW&>e w ~ I. Li.

o.:a

a.a-P-~~~~-1-~~~~--1-~~~~-+-~~~~--+~~~~----i

o.o .l.a a.a 3.a 4.0 ~.o

Dincnsionless Reaction TiMe <WAT Reference Particle>

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Chapter 7. Summary of the Applications, Limitations and Extensions of the Heterogenous, Columnar Model.

The previous chapter presented the development of the heterogenous columnar model. Conceptually, the modelling strategy involved the division of the waste deposit into columnar sections and then determining the release of hazardous constituents from a single column. The release of hazardous constituents from a single column is determined by making use of a one-dimensional, non-catalytic, packed-bed type reactor model. The reactor model is derived by applying a fluid reagent mass balance to the column. Within the column, fluid reagent is consumed due to chemical reactions which occur both on the surfaces and within the waste particles. This consumption is modelled using a particle scale, chemical reaction model which also determines the release of hazardous constituents into the bulk fluid surrounding the particles. Once the hazardous constituents are released from the particles, they are assumed to be transported out of the column by the bulk fluid flow through the column.

This chapter summarises the applications, limitations and possible extensions of the heterogenous columnar model. The first section compares this model to the model of · Roman et al. [1974] and the columnar model of Dixon [1992, 1993]. As previously discussed, although these last two models were developed as precious metal leaching models, several similarities exist between precious metal leaching from ores and the leaching of hazardous constituents from waste particles. Most importantly, this section highlights the advantages of the heterogenous columnar model, which was specifically designed to model the leaching of hazardous constituents from waste deposits, over the heap leaching models.

The next section discusses potential engineering applications of the heterogenous columnar model. In particular, this section summarises the type of information which can be determined using the model and demonstrates how this information can be used to improve waste deposit design and to choose upstream processing options which result in more stable wastes.

The limitations of the heterogenous columnar model, which are largely due to the simplifying assumptions which have been made, are then reviewed and methods to remove these limitations are presented.

Finally, a statement of the significance of this work is made.

7.1 Comparison of the Hetero&enous Columnar Model to the Model of Roman et al. (19741 and the Columnar Model of Dixon (1992, 19931.

The heterogenous columnar model is comparable to the model presented by Roman et al. [1974] and the columnar model presented by Dixon [1992, 1993]. All of these models

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approximate deposit or heap performance by determining the performance of a single column packed with waste or ore partides. Further, all three models approximate the fluid flow through the deposit or heap as perfect plug flow and include a saturation index. This parameter is included to account for unsaturated conditions in the waste deposit or ore heap. The heterogenous columnar model includes a global wetting parameter, presented in section 6.3, to accommodate the effects of incomplete particle wetting on the release of hazardous constituents. Since the fluid reagent distribution systems in ore heaps are specifically designed to maximise particle wetting, incomplete particle wetting is not considered by Roman et al [1974] or Dixon [1992, 1993].

Table 7 .1 summarises the properties of the heterogenous columnar model and the heap leaching models of Roman et al. [1974] and Dixon [1992, 1993].

Table 7 .1. Summary of the properties of the heterogenous columnar model and the heap leaching models of Roman [1974] and Dixon [1992, 1993].

Fluid flow model:

Chemical reaction model:

-

Heterogenous Columnar Model.

Plug flow model.

Constant or variable fluid flow into deposit.

Includes a saturation index and a global wetting factor.

Particle scale model which includes the effects of intrinsic chemical kinetics, diffusion and hazardous constituent location on contaminant release.

Parameter spec. as a function of particle size is particularly suited to waste particles.

Heap Leaching Model of Roman et al.

Plug flow model.

Constant fluid flow into heap.

Only includes a saturation factor.

Particle scale shrinking core model which assumes that diffusion of the fluid reagent is rate limiting.

111

Heap Leaching Model of Dixon.

Plug flow model.

Constant fluid flow into heap.

Only includes a saturation factor.

Particle scale model which includes the effects of intrinsic chemical kinetics, diffusion and precious metal location on metal release.

Parameter spec. as a function of particle size is particularly suited to ore particles.

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7.1.1 Comparison to the Model of Roman et al. (19741.

The main difference between the heterogenous columnar model and the model of Roman et al. [1974] is in the method used to determine the rate of hazardous constituent or precious metal release from the individual particles. Roman et al. assumed that the release of the precious metals was dominated by diffusion of the fluid reagent into the ore particles and thus made use of a diffusion controlled, shrinking core reaction model. As previously discussed in section 2.4, this model cannot include the effects of intrinsic chemical kinetics, precious metal location within the ore particle or competing chemical reactions on the rate of precious metal release.

The heterogenous columnar model developed here employs a chemical reaction model which is based on a fluid continuity equation at the particle scale. This model, which was used by Dixon [1992] and summarised in Chapter 4, is used to determine the release of hazardous constituents from waste particles. (The particle scale model of Dixon is distinct from his columnar model.) This approach is capable of including the effects of intrinsic chemical kinetics, intra-particle diffusion, hazardous constituent location within the particle and competing chemical reactions on the rate of release of the hazardous constituents.

The ability of the particle scale chemical reaction model, which is incorporated into the heterogenous columnar model, to include the effects of competing chemical reactions is particularly important when describing release of hazardous constituents from waste particles. The reason for this is that most waste particles consist of two or more solid reactive species present in significant concentrations which compete for fluid reagent. As long as the voidage of the waste particles remains fairly constant, this competition has the effect of reducing the available fluid reagent for each reactive species. Thus the release of an individual species is slowed down for each additional competing reaction which occurs. In contrast, competing reactions which result in an increase in the voidage of the particles may result in increased leaching rates. The reason for this is due to the fact that an increase in the particle voidage will result in an increased effective diffusivity of the fluid reagent into the waste particles. Only the case of constant particle voidage has been considered in this work. The extension of the model to include a dynamic particle voidage is discussed in the next section.

It is important to note that the particle scale chemical reaction model will reflect diffusion control, chemical kinetic control or an intermediate condition depending on the Kpi parameter specification. The Kappa parameter, Kpi• defined in $ection 4.2,represents the ratio of the chemical reaction rate within a particle to the rate of diffusion of fluid reagent into the particle. As such, the Kpi parameter corresponds to a Damkohler number of the second type [Aris 1975]. A high value for Kpi implies that the reaction is controlled by diffusion of the fluid reagent into the particle. Similarly, a very low value for Kpi implies that the reaction is controlled by the intrinsic chemical kinetics of the reactions. Figure 4-2 showed reagent profiles for several parameter combinations. Note that diffusion controlled reactions result in steep fluid reagent and solid reactant gradients within the particles. In contrast, reactions which are controlled by the intrinsic chemical kinetics exhibit very flat fluid reagent and solid reactant gradients.

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7.1.2 Comparison to the Columnar Model of Dixon [1992, 19931.

Dixon [1992, 1993] has also incorporated the particle scale, chemical reaction model into a column type model to predict the performance of heap leaching operations. Probably the most important difference between his model and the heterogenous columnar model developed here is the manner in which the particle scale model parameters have been determined as a function of particle size. In summary, it is desirable to determine or specify parameters for a single size class of particles, termed a reference size class, within the column. The parameters of all the other size classes of particles are then determined from the reference size class parameters using suitable mathematical relationships. The reason why this approach is desirable is that it eliminates the need to define suitable particle scale model parameters for each size class of particles. This greatly reduces the number of parameters required.

Dixon [1992] presented mathematical relationships for the particle scale model parameters as a function of particle size for ore particles. These relationships, discussed in section 5.2.1,were found not to be applicable to waste particles because they required information about precious metal location in the ore particles as a function of particle size. This information was determined from a knowledge of ore preparation. Hazardous constituent location in waste particles is usually highly size specific and a result of the processing operations which generate the waste. For this reason, additional mathematical relationships, which are specifically applicable to the determination of the model parameters for waste particles as a function of particle size, have been proposed in section 5.2.2. It is worth noting that these relationships are more complex than those defined by Dixon, but, under appropriate conditions, will simply to those of Dixon. This implies that the heterogenous columnar model developed in this work can be applied to both the leaching of hazardous constituents from waste deposits as well as to precious metal leaching from ore heaps. These equations have been included in a bulk fluid reagent mass balance. These aspects and an appropriate solution strategy have been discussed in section 5.3 and 5.4 respectively.

The next main difference between the columnar model of Dixon and the heterogenous columnar mod_el is that the new model includes the possibility for a variable fluid reagent flow into the deposit. The inclusion of a variable fluid velocity into the model is important in order to model the effects of periodic rainfall on the release of hazardous constituents from waste deposits. Further, work at the University of Cape Town [Petersen 1994, 1995] has revealed that fluid flow through lysimeter columns can vary significantly during the experiment. Thus, in order to fit the heterogenous columnar model to lysimeter data, it must be capable of including variable fluid reagent flow into the deposit. The strategy adopted to include a variable fluid reagent flow into the heterogenous columnar model is identical to the strategy adopted to include this effect into the macroscopic, lumped parameter model which was discussed in section 3.4. In summary equation (6-9) is redefined in a manner similar to equation (3-29). This equation is then used to determine the appropriate time interval for each successive iteration in time.

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Another difference between the models is that Dixon [1993] has included a mass balance equation to include the effects of dissolved species transport within the particles. Due to time limitations, this was not included in the heterogenous columnar model. The inclusion of this mass balance equation into the heterogenous columnar model is discussed in a later section in this chapter. The importance of including this aspect into the model is that it will extend the applicability of the model to cases where dissolved species transport within the waste particles is significant.

7 .2 A Summary of the Potential Engineering Applications of the Heterogenous Columnar Model.

The heterogenous, columnar model, described in the preceding sections, has two particular attributes which make it attractive in the engineering design of better waste deposits. The first of these attributes is that it is capable of determining the relative contributions of the intrinsic chemical kinetics and the diffusion of fluid reagent into the particles to the release of hazardous constituents. These rate terms are in tum a function of the hazardous constituent location within the particles, the size distribution of the particles, competing chemical reactions and the bulk fluid reagent flow. The second attribute is that the parameters required for this model can be determined from a simple CSTR type experiment. One particular advantage of being able to determine the model parameters from CSTR type experiments is the short duration of these experiments. This implies that the potential release of hazardous constituents can be determined much more quickly than existing methods which are fitted to lysimeter data. This ability will enable the minerals processing industry to determine a priori the suitability of various wastes for disposal in waste deposits. Another distinct advantage of using CSTR tests to determine the model parameters is that CSTR tests are much cheaper to conduct than lysimeter experiments. This implies that more wastes can be tested prior to disposal and that samples from existing waste deposits, which could not be tested previously due to the expense of lysimeter experiments, can now be tested.

7.2.1 Improved Deposit Desi2n based on Results from the Hetero2enous Columnar Model.

Once the particle scale model parameters for a given waste stream have been determined, the heterogenous columnar model can be used to investigate the behaviour of a typical deposit which would contain this material. The results of the heterogenous columnar model will not only give an indication of the release of hazardous constituents from the waste deposit but can also be used to improve the disposal strategy to minimise the release of hazardous constituents.

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Deposits Which React in a Zone-Wise. Fluid Reagent Limited Manner.

As an example, consider the case where the results of the heterogenous columnar model indicate that the deposit is reacting in a zone-wise,fluid reagent limited manner. The rate of the chemical reactions occurring in the particles of such deposits is relatively fast compared to the rate of fluid flow through the deposit. Even if the breakthrough curves determined by the heterogenous columnar model are acceptable in terms of the concentrations of the hazardous constituents, deposits of this nature present an environmental risk. The reason for this is that the release of hazardous constituents is only limited by the amount of fluid flowing through the deposit. Should this increase, so too would the rate of release of hazardous constituents. It is a high priority therefore to keep deposits which react in a fluid reagent limited manner dry. This could be achieved by using suitable liners to prevent rain or ground water from percolating through the deposit.

As an alternative to keeping the deposit dry to limit the release of hazardous constituents, pretreatment options for the waste could be investigated which would slow down the rate of release of hazardous constituents at the particle level. One likely factor which would result in relatively fast chemical reactions would be if a significant fraction of the hazardous constituents are concentrated onto the surface of the particles. (These reactions would be relatively fast because they do not experience any fluid reagent diffusional resistances.) If significant concentrations of hazardous constituents are known to exist on the surface of the particles, their release could be reduced by removing these components in a pretreatment process. Surface hazardous components could be removed from the particles by making use of an active leach procedure. It may be possible to purify the leachate generated by such a process and return the 'contaminants', which are often heavy metals, to the process which generated the waste. If it is not feasible or economical to pretreat the particles using a leach procedure then alternative methods to stabilise the waste need to be investigated. One alternative method would be to agglomerate the particles into larger particles using suitable binding agents. In this process, much of the external surface area of the original particles would be incorporated into the bulk of the larger agglomerated particle. Before the fluid reagent could react with the hazardous constituents it would need to diffuse through the agglomerated particle to the location of the hazardous constituents. Binding agents usually exhibit a buffering capacity with respect to the fluid reagent. This too, would slow down the release of the hazardous constituents from the particles due to the competition between the binding agent and the hazardous constituents for the fluid reagent. Suitable particle scale model parameters can be determined for such agglomerated particles using a CSTR experiment. These parameters could then be used to determine whether the agglomeration would improve the overall deposit performance.

In the case where the release of hazardous constituents from particles is fast and where there is not a significant concentration of hazardous components on the surfaces of the particles, methods to retard the effective chemical reaction rates need to be investigated. The first way in which this can be achieved would be to enhance the diffusional resistances which limit the fluid transport into the particle. As before, this can be achieved by agglomerating the particles using suitable binding agents. Alternatively, attempts can be made to slow down the intrinsic kinetics within the particle by

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chemically altering the speciation of the hazardous constituents. Usually little is known about the complex chemistry of waste particles and any attempts to alter the intrinsic chemical kinetics will most probably require extensive experimentation. In contrast, note that the only instance in which agglomeration will not result in reduced effective chemical reaction rates will be when the intrinsic chemical kinetics are many orders of magnitude slower than the rate of fluid reagent diffusion into the particle. Such a situation will be easy to identify because the particles will react in a totally homogenous manner. (This situation corresponds to a very low Kappa, Kpi• parameter.)

Deposits Which React in a Homogenous Manner.

In contrast to deposits which react in a zone-wise, fluid reagent limited manner, some deposits react in a homogenous manner. The release of hazardous constituents from these deposits is not limited by the flow of fluid through the deposit but rather by the release of hazardous constituents from the individual waste particles. These deposits present little or no environmental risk if the results of the heterogenous, columnar model indicate that the release of hazardous constituents is acceptable. The reason for this is that the . individual particles within the deposit, release hazardous constituents at a sufficiently slow rate which the natural environment can assimilate. An increase in the fluid reagent flow through the deposit will not increase the rate of hazardous constituent release.

Should the results of the heterogenous columnar model indicate that the release of hazardous constituents from the deposit is unacceptable, then methods to slow down the effective chemical reaction rates similar to those discussed in the previous section need to be investigated.

7.2.2 Usine the Heteroeenous Columnar Model to Choose Upstream Processes which would Result in More Stable Wastes.

The properties of a waste stream are dictated by the upstream processes from which it arose. These properties include the chemical composition of the waste stream, the location of the hazardous constituents within individual particles and the size distribution of the particles within the waste stream.

Using the heterogenous columnar model, the particle characteristics which contribute most to the release of hazardous constituents from waste particles can be identified. This information can then be used to identify the upstream processes which result in the waste particles exhibiting the particular characteristic. Alternative processing options can then be investigated which would result in more stable wastes.

As an example, should the results of the heterogenous columnar model indicate that it is mainly the smaller particles within the size distribution of waste particles which are responsible for the release of hazardous constituents (due to smaller diffusional resistances in small particles), then the upstream processes which produce these particles should be identified and investigated. In this case, alternative processes which still

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achieve the desired process goal but which do not produce the small particles would be preferred.

Equally, the heterogenous columnar model could indicate that significant concentrations of hazardous constituents on the surfaces of particles are responsible for the release of contaminants. In this case, process options which aim at recovering the 'contaminants' from the wastes should be investigated.

7 .2.3 Using the Heterogenous Columnar Model to Asses the Risks and Liabilities Associated with Existing Waste Deposits.

South Africa is not unique in the fact that it has many waste deposits which could pose a significant environmental hazard due to the generation and release of leachate. For various reasons, which include financial constraints of conducting lysimeter experiments and ineffective legislation with respect to the disposal of industrial wastes, the risks associated with many of these deposits is unknown. The heterogenous columnar model can be used to estimate the potential leachate generation of these deposits and thus determine the risks associated with them. This would be achieved by conducting a CSTR test on a single size class of the material in the deposit being examined. As before, this would be used to determine appropriate model parameters for the heterogenous columnar model which would then be used to predict the deposit performance. This information could then be used to estimate the risks associated with these deposits and to identify which of the existing deposits require remediation.

7 .3 Limitations and Possible Extensions of the Hetero2enous Columnar Model.

The heterogenous columnar model has been presented as. a suitable model to describe the release of hazardous constituents from waste deposits. The applicability of this model can be .extended by beginning to remove the simplifying assumptions which were made during the model development. This section summarises the limitations of the model and suggests methods to address these limitations.

7.3.1 Incorporation of External Mass Transfer Resistances into the Model.

The heterogenous columnar model assumes that the mass transfer of the fluid reagent between the bulk fluid, which is the fluid between the particles, and the surfaces of the particles is negligible. Such an assumption is only valid when the effective reaction rate of hazardous constituent release is slow compared to the supply of fluid reagent to the particle surface. In cases where this assumption does not hold, external mass transfer resistances need to be accounted for explicitly.

Equation (5-1) is a mass balance equation which relates the consumption of the fluid

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reagent within the particles to the overall bulk fluid reagent concentration between the particles. This equation is valid only when external mass transfer resistances are negligible and needs to be modified when external mass transfer resistances are important. The modification involves relating the consumption of the fluid reagent within the particles to the rate of fluid reagent trapsfer to the particles. Equation (5-1) as well as the new equation are summarised below:

where V Part.

VLiq.

dCA BUllc

dt

is the total volume of the particles; and; is the total volume of fluid reactant.

(5-1 or 7-1)

This equation is equivalent to:

de A sulk

dt (7 -2)

The new equation is:

where~

~

CA.Bulk

CA,Surface

(7 -3)

is the mass transfer coefficient, determined using correlations for Sherwood numbers or j 0 factors; is the total extemal area of the particles; is the bulk fluid reagent concentration; and; is the concentration of the fluid reagent on the particle surface.

Suitable correlations are required to determine the external mass transfer rate, ~. before the heterogenous columnar model can be applied to cases where external mass transfer resistances are important. Several correlations are presented in the literature [Agarwal 1988; Kawase and Ulbrecht 1985; Wakoa and Funazkri 1978; Nelson and Galloway 1975; Mochizuki and Matsui 1973; Calderbank 1967; Wilson and Geankoplis 1966; Rowe and Claxton 1965; Pfeffer 1964; Ranz 1952; Smith 1981] for Sherwood numbers and j 0 factors as a function of Reynolds and Schmidt numbers. The Sherwood number is a ratio of the rate of convective mass transport to the rate of molecular mass transport at the particle surface and can be used to determine the external mass transfer

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coefficient. Similarly j 0 factors can be used to determine external mass transfer coefficients.

It is important to note that the external mass transfer rates are normally defined in terms of average mass transfer coefficients [Smith 1981]. Thus a single value of the mass transfer coefficient can be -used to describe the rates of transfer between the bulk fluid phase and the particle surface. The error introduced in using an average coefficient is not as serious as might be expected, since the correlations for the mass transfer coefficient, ~'are based on experimental data for packed beds of particles [Smith 1981].

7.3.2 Inclusion of Intra-Particle Dissolved Species Transport Resistances into the Model.

The intra-particle dissolved species transport resistances have been assumed to be negligible compared to the diffusion resistances of the fluid reactant into the particles and the chemical reaction rates within the particles. As discussed in section 7 .1.2,Dixon (1993] has included these effects into his columnar model. The strategy adopted was to apply a mass balance equation for each dissolved species at the particle level. The equations derived are very similar to equation ( 4-6) which represented a mass balance for the fluid reagent at the particle level. Equation (4-6), and the mass balances for the dissolved species are summarised as:

(4-6 or 7 -4)

[ a2ci 2 aci J ( il>pi aci n. --+--- +po 1-eo)k .cpi CA=Eo at 1 ar 2 I ar pi (7 -5)

where Ci dissolved hazardous constituent concentration of species i.

Equation (7-5) can be used to determine the dissolved concentration of hazardous constituents within the particle and at the particle surface. Should external mass transport of the dissolved hazardous constituents from the particle to the bulk fluid be significant, a suitable mass transfer correlation, similar to the correlations described in section 7. 3 .1, would be required to determine the bulk concentration of dissolved hazardous constituents. If external mass transport resistances are negligible, then a simple mass balance can be used to determine the bulk concentration of dissolved hazardous constituents.

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7.3.3 Inclusion of Matrix Dissolution and Hazardous Constituent Re-Precipitation in the Hetero2enous Columnar Model.

Neither matrix dissolution or the re-precipitation of dissolved hazardous constituents have been incorporated into the heterogenous columnar model. Matrix dissolution refers to the process of the waste particles becoming more porous due to significant quantities of the particle being dissolved during the life span of a deposit. It is unlikely that the effects of matrix dissolution will, be easily incorporated into the particle scale chemical reaction model. The reason for this is that the particle scale model makes use of an effective diffusivity De to determine the diffusion of fluid reagent into the particle. As matrix dissolution takes place, the voidage of the particles will increase. A larger voidage within the particles will substantially effect the rate of diffusion of fluid reagent into the particles. Thus before the effects of matrix dissolution can be incorporated in the particle scale model, a suitable model for the effective diffusivity, De, would need to be determined. It is worth noting that simple models for the effective diffusivity such as the parallel pore more model, described by Smith [1981] and summarised in equation (7-6), are inappropriate. The reason for this is that the tortuosity factor used in the models is also a function of matrix dissolution and would be an unknown in the model.

where De D €

0

D =ED e 0 .

effective diffusivity; actual diffusivity; particle voidage; and; tortuosity factor.

(7 -6)

Once the hazardous constituents have been dissolved there is a good possibility for them to reprecipitate either within the particle or onto the surfaces of surrounding the particles. These aspects need to eventually be incorporated into the heterogenous columnar model.

7.3.4 Inclusion of More Realistic Hydrodynamic Flow Models into the Hetero2enous Columnar Model.

The only fluid flow pattern through the deposit which was considered in the heterogenous columnar model was perfect plug flow. As discussed in section 2 .1. 2, the hydrodynamic flow patterns within waste deposits are often far more complex than a simple plug flow pattern. These irregular flow patterns need to be incorporated into the heterogenous columnar model.

The simplest manner in which 'non-ideal' flow patterns can be inco.rpOrated into the heterogenous columnar model would be to make use of a one parameter fluid dispersion

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model. In this approach any back m1xrng and short circu1tmg of fluid reagent is considered as fluid dispersion. A suitable one parameter fluid dispersion model which is applicable to columnar reactors is the 'tanks-in-series' approach described by Levenspiel [1972]. In this approach, the reaction in the column is approximated by a number a discrete, equi-sized continuously stirred tank reactors in series. The single parameter in the approach is the number of tanks-in-series which are required to approximate the fluid flow behaviour within the columnar reactor. A tracer study which yields the residence time distribution of the column can be used to determine this parameter. This technique is described by Levenspiel [1972].

This approach would be easy to implement in the heterogenous columnar model. In section 6.1 a modelling strategy for the heterogenous columnar model which was based on heap leaching models was described. In summary the column was assumed to consist of a number of discrete disks. Within each disk the fluid reagent concentration was assumed to be uniform. It was noted in section 6.1 that the column would need to be divided into a sufficient number of disks in order· to ensure that this assumption would be valid. In effect, this corresponds to the case of 'N-oo' in the tanks-in-series approach where N represents the number of tanks in the chain. In reality, the number of 'tanks' or disks required to model perfect plug flow is finite and is determined as the number of disks beyond which model accuracy does not improve. This number of disks represents the minimum number of disks which are required within the column to adequately simulate perfect plug flow in the column. In effect, the 'inaccuracies' introduced when fewer disks are used can be interpreted as fluid dispersion and can be taken as an indication of the performance of columns which exhibit irregular flow patterns. The performance of a particular column which exhibits irregular flow patterns can be approximated by conducting a tracer experiment on the column and using the residence time distribution obtained to determine a suitable number of tanks, N, which will approximate the flow patterns within that column. By using the heterogenous columnar model with N disks, the performance of the column can then be estimated.

More complex multi-parameter dispersion models will be required as the flow patterns within a deposit become more irregular. These models consider the column to consist of several hydrodynamically distinct regions which can each be described by plug flow, dispersed plug flow and mixed flow models. These models were discussed briefly in section 2.5.

To improve the ability of the heterogenous columnar model to predict the release of hazardous constituents under truly unsaturated conditions, the ground water flow equations used by Demetracopoulos et al. [1986] can be incorporated into the model. These equations, presented in section 2.3.2,determine the saturation and fluid velocity as a function of position within the column and time. These factors are included in the heterogenous columnar model by updating equation (6-4). The updated equation can be summarised as:

ac ac a n E Col Acol =-u Acal -c __!::! + "C1 r

Col % Sat: A ~ at az Col az i=l ai (7 -7)

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where the Col% sat is now a function of position within the column and time. (Col% sat

corresponds to 01 Ec01 , where e is the moisture content used in equation (2-2) and (2-3).)

Note that the second term on the right hand side of the equation is a direct result of the divergence of the velocity field within a volume element in the column no longer being equal to zero. (Compare equation 3-1, 3-4 and 3-5.)

7.4 Statement of the Significance of the Work Presented in this Thesis.

Waste deposits which contain wastes from the minerals processing industry pose environmental hazards due to the possibility of leachate generation and the subsequent · release of this leachate into the environment. The impacts of waste deposits have been traditionally investigated using lysimeter experiments. These experiments are both very time consuming and costly. This and other factors, such as ineffective legislation with respect to waste disposal strategies, have resulted in a limited study of the environmental impacts of disposing of mineral wastes in waste deposits.

Due to increased environmental awareness, the minerals processing industry is being encouraged to investigate the environmental impacts of its disposal strategies. As such, suitable modelling strategies which could predict deposit performance would be most useful. The reason for this is that these models could be used to investigate the potential for waste deposits to pollute the environment. If sufficiently detailed, these models could also be used to identify the major contributing factors to the release of hazardous constituents from waste deposits. This information could then be used to engineer better waste deposits in future. Models could also be used to investigate modifications to the upstream processes with the aim of producing more stable wastes. Equally as important, the risks associated with the many existing waste deposits could be determined and remedial action taken before a catastrophic situation arises.

The work presented in this thesis is an investigation into identifying suitable modelling strategies to describe the release of hazardous constituents from waste deposits. The first model investigated was a macroscopic, lumped parameter model. This model was investigated due to its inherent simplicity and its ability to characterise a deposit as a reacting entity. The investigation into this model revealed that it had limited applicability to identify the main factors which result in the release of hazardous constituents from waste deposits. This implies that this model has limited applicability in the design of new deposits. Further, the parameters required for the macroscopic lumped parameter model are determined from fitting the model to lysimeter data. This too is a limitation due to the fact that lysimeter experiments take a minimum of a few months and can take up to three years to complete. For these reasons a second model, termed the heterogenous columnar model was investigated.

The heterogenous columnar model describes the release of hazardous constituents from the individual particles within a waste deposit and relates this release to the overall

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deposit performance. This model has been developed to apply specifically to the release of hazardous constituents from waste deposits. The heterogenous columnar model has the capability of identifying the main factors which can be associated with the release of hazardous constituents. As an example, the heterogenous columnar model can be used to determine the relative contributions of the intrinsic chemical kinetics of the waste particle and the diffusion of fluid reagent into the particle to the release of hazardous constituents. Equally, the significance of the bulk fluid flow through the deposit compared to the effective rate of hazardous constituent release can be determined. This information could be used in the engineering design of waste deposits and was discussed in section 7.2.1. Further, this information could be used to investigate upstream processing options which would result in more stable wastes. This was discussed in section 7.2.2.

The heterogenous columnar model has the distinct advantage that the parameters which it requires can be determined from CSTR type experiments. Probably the most important advantage of being able to determine the heterogenous columnar model parameters from CSTR experiments is that CSTR type experiments are considerably quicker than lysimeter experiments. This means that the large delay times associated with the traditional lysimeter experiments can be eliminated. Using the heterogenous columnar model, the minerals processing industry_ would be able tp determine the suitability of a particular waste for disposal in a waste deposit. The second significant advantage of being able to determine the model parameters from a CSTR type experiment is the relatively low costs associated with these experiments when compared to lysimeter experiments.

The heterogenous columnar model can also be used to investigate the risks associated with existing waste deposits. This would be achieved by collecting samples from these deposits and conducting a CSTR type experiment on a single size class of the particles. The data from this experiment could be used to determine the heterogenous columnar parameters as discussed in section 5.8 and 6.6. The heterogenous columnar model could then be used to estimate the release of hazardous constituents from these deposits. This information could be used to asses the risks with these deposits and to identify which deposits require remedial attention in order to prevent pollution of the environment.

This work has been a first attempt to identify or develop suitable modelling strategies to determine the release of hazardous constituents from waste deposits. The heterogenous columnar model has been identified as a possible candidate for this purpose. This model has been applied to the leaching of precious metals from ore particles and the capability of the model to describe and predict the leaching behaviour is encouraging. The verification of the model against data from waste deposits or lysimeter experiments still needs to be completed. The type of data required for this purpose has been summarised in section 6. 7. Once the heterogenous columnar model has been verified against waste leaching data it may start to provide the minerals processing industry with the information which it so desperately requires in order to dispose of their wastes in a responsible manner which will not pose a threat to the environment.

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Welty J.R., Wicks C.E. amd Wilson R.E. ,Fundamentals of Momentum. Heat and Mass Transfer, John Wiley and Sons, Singapore, 1984.

Wilson E.J. and Geankoplis C.J. "Liquid Mass Transfer at Very Low Reynolds Numbers in Packed Beds", Industrial and Engineering Chemistry Fundamentals, 5(1):9-14, 1966.

Zimmerman, S.P., Chu, C.F., and Ng, K.M. "Axial and Radial Dispersion in Trickle Bed Reactors with Trickling Gas-Liquid Down-Flow. ", Chemical Engineering Communications 50:213-240, 1987.

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Appendix I. Summary of the Method of Characteristics.

This appendix presents a summary of the method of characteristics which is used to solve first and second order hyperbolic partial differential equations. Much of the matter presented in this section has been summarised from Chapter 9 of the book Analysis and Solution of Panial Differential Equations by Robert L. Street [1978].

The solution of first-order or second-order partial differential equations with a single dependent variable and two independent variables can be visualised as a surface in (x,y,z) space. Analytical geometry can be used to enhance an understanding of the solution technique for such equations. This is particularly valid for initial-value problems in which we expect the solution to propagate from the region on which the initial data was specified.

In the case of first-order and hyperbolic second-order equations, information from the initial data propagates over well-defined paths in the surface representing the solution. These propagation paths are called characteristics. A knowledge of the existence of characteristics gives considerable insight into the expected behaviour of a problem's solution, even before the solution is known.

This summary is restricted to first-order equations which involve a single dependant variable and two independent variables.

The general first-order partial differential equation in two independent variables (x,y) is:

where

F(x,y, z,p, q) =O

az p=­ax (Al -2)

(Al-l)

(Al-3)

If equation (Al-1) is a quasi-linear equation, it can be written as:

Pp+Qq=R (Al-4)

where P,Q and R are functions of x,y,and z but not of p or q. It is assumed that P,Q and R, together with their first derivatives, are continuous in the region of the problem under consideration. Further, P and Q are assumed not to vanish simultaneously. This implies:

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(Al-5)

First-order equations arise in many physical systems. Equations (3-5) and (3-23) were both first-order hyperbolic partial differential equations. These equations model the bulk flow and chemical reaction of a fluid reagent through a column. These equations, which are so-called Convection Equations, are identical to the quasi-linear equation (Al-4). To demonstrate this, equation (3-23) has been written below in exactly the same form as equation (Al-4):

where

1 =P (Al -7)

aa. +DGl aa. =-DG2a.a418.1

ai' ae 81

DG2=Q (Al-8)

(Al-6)

G 4's1 -D 2a.aBi =R (Al-9)

The solution z(x,y) to the quasi-linear equation (Al-4) can be represented as a surface in (x, y ,z) space shown in Figure A 1.1. This surface is called an integral surface because it represents the solution or 'integral' of the partial differential equation. The integral surface for (Al-4) is represented by the formal identity:

I(x,y,z)=z(x,y)-z (Al-10)

Figure Al.1 An integral surface representing the solution to equation (Al-4).

l(x,y, z) = z(x, y) - z = 0

z

Taking the differential of equation (Al-10) will, from analytical geometry considerations,

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result in the. equation for the tangent plane to the integral surface at any point. The equation for the equation plane is thus:

or

ar dx+ ar d + ar =o ax ay y az

az az -dx+-dy-ldz=O ax ay

(Al-11)

(Al-12)

Equation (Al-12) is nothing more than the total differential and can be written as:

dz=p dx+q dy (Al-13)

Equation (Al-13) is a tangent plane to the solution plane at any point. Accordingly, the vector N=pi+qj~lk; that is, the vector (p,q,-l);is normal to the integral surface, depicted in Figure Al .1, at any point.

The scalar product of N and the vector (P, Q,R) is zero because:

(P, Q, R) · (p, q, -1) = (Pi+Qj+Rk) · (pi+qj-lk)

= Pp+Qq-R = 0

(Al-14)

from equation (Al-4). Thus (P,Q,R) is perpendicular to N. Consequently, (P,Q,R) is tangent to the integral solution surface at every point and lies in the plane of the tangent equation (Al-13). This means that the first-order equation (Al-4) can be regarded as a geometric requirement that any integral or solution z(x,y)through the point (x,y ,z)must be tangent to the vector (P, Q,R). In fact, by beginning at some point on the integral surface, one line which lies in the integral surface can be determined from the known tangent vector (P,Q,R). This line is termed a characteristic. By determining sets of characteristics, the solution surface can be generated.·

Stated in another way, the vector (P,Q,R) has been determined to be tangent to the solution surface at all points. A single line in the integral surface can be determined by starting on a point on the integral surface, moving in the direction of (P, Q,R) and determining the curve which is tangent to (P,Q,R).

Suppose tha~ the position vector r of a point on a characteristic curve 1s:

r=xi+yj+zk (Al-15)

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This vector can be expressed parametrically in terms of distance s along a particular curve:

r(s)=x(s)i+y(s)j+z(s)k (Al-16)

and the tangent vector to the curve at a particular point is:

ar = ax i + ay . + az k as as as 1 as

(Al-17)

The vector (dxlds;dy/ds;dzlds) is tangent to the characteristic curve and the solution or integral surface. (P, Q,R) is also tangent to the solution or integral surface thus the two vectors are co-incident and their components must thus be proportional. This implies:

dx/ ds = dy/ ds =dz/ ds (Al-18)

or

p Q R

dx= dy =dz p Q R

(Al-19)

The system of equations represented in (Al-19) must be satisfied by any characteristic in the solution surface. Thus the partial differential equation (Al-4) can be converted into a system of ordinary differential equations represented by (Al-19). Equivalent systems of equations (Al-19) are:

dy= Q dz R (Al-20) ---dx p dx p

or

dx p dz R (Al-21) --- ---dy Q dy Q

Equations (Al-20) or (Al-21) are ordinary differential equations which can be solved by conventional means.

F: I WP51 \THESIS\GDTH2AP1 .1

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Appendix II. Solution Algorithm and Code for Model4Dl.PAS and Model4D2.PAS.

Model4 represents the computer routines for the Macroscopic, Lumped Parameter Model Presented in Chapter 3.

Solution Algorithm for Model4D.

Start. I Set/Initialise Variables.

Iterate in Time.

Determine Corresponding Time Increment.

Calculate the appropriate Alpha and sigma vector values within the column.

Increment Fluid Vectors.

I

Graph Breakthrough Curves

I End.

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07/2

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95

13:5

2 Fi

lena

me:

M

ODEL

4D1

.PA

S Pa

ge

Prog

ram

Mod

el4D

1;

(Mod

el4D

1 ( ( ( (

Thi

s pr

ogra

m

is a

cod

e fo

r th

e co

nvec

tive

flu

x m

odel

w

hich

in

corp

orat

es u

nste

ady

state

flo

w.

Dea

ls w

ith

var

iab

le s

oli

d r

eact

ion

ord

ers.

N

ote

that

th

is c

ode

uses

the

NE~

DIM

ENSI

ONLE

SS

GROU

PS

defi

ned

on

18 J

anua

ry 1

995.

} } } } }

(Cod

ed:

Gra

ham

Dav

ies.

}

C

Dep

artm

ent

of

Che

mic

al

Eng

inee

ring

. }

( U

nive

rsit

y of

C

ape

Tow

n.

} (

19

Janu

ary

1995

. }

C

10 M

ay

1995

-

Upd

ated

. }

<===

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

==}

(Dec

lara

tion

s:

}

uses

cr

t,st

dh

dr,

gra

ph

,wo

rld

dr,

seg

rap

h,i

nte

gra

t;

var Su

pVel

File

,Exp

Dat

a

SupV

elD

ata

Dat

a

:tex

t;

:arr

ay[1

.• 2

,1 .

• 2]

of d

oubl

e;

:arr

ay[0

.. 2

56,1

.• 3

] of

dou

ble;

ART

,ART

P1,S

RT

1,SR

T_2

,SR

T_3

,Sol

SRT

_1,S

olSR

T_2

,Sol

SRT

_3

Hol

dSRT

1,

Hol

aSR

T 2,

Hol

dSR

T 3

Dat

aSet

X,D

ataS

etY

;lnt

erG

_1,T

nter

G_2

,lnte

rG_3

C

onv

1,C

onv

2,C

onv

3 BT

CA~T

,BTC

S~T_

1,BT

CSRT

_2,B

TCSR

T_3,

Time

Vect

or

lntl

eng

th,l

ntl

eng

thC

rit,

Del

ta t

,Del

taT

,Arb

Val

ue

Cum

Tim

e,E

rror

Sllll

-

-DG

2 1,

DG

2 2,

DG

2 3,

DG

3 1,

DG

3 2,

DG

3 3

,0rd

1,0

rd 2

,0rd

3

Voi

aage

,Len

gth,

usta

r,D

elta

E-

--

--

GfM

ax_X

,GfM

ax_Y

Arb

lnde

x,S

ubln

terv

alln

dex,

Con

tinu

e,P

rint

Fil

terl

ndex

V

ecto

rlnd

ex,H

ardC

opy,

erro

r,N

o of

Dat

aPoi

nts,

Pos

itio

n N

,Nll

llS

ubln

t,lt

erat

ions

,Pri

ntF

ilte

r N

o_of

_P

oint

s

Tim

eCou

nter

NS,

Len

gthS

DG

2 1S

,DG

2 2S

,DG

2 3S

,DG

3 1S

,DG

3 2S

,DG

3 3S

G

Lao

el2,

GL

abel

4,G

[abe

l5 -

--

Sho

rtV

ecto

r;

Sho

rtV

ecto

r;

Ver

ylon

gVec

tor

Ver

yLon

gVec

tor

Ver

yLon

gVec

tor

:Dou

ble;

:D

oubl

e;

:Dou

ble;

:D

oubl

e;

:Rea

l;

: In

teg

er;

: In

teg

er;

: In

teg

er;

: In

teg

er;

:Lon

glnt

;

Str

ng

Str

ng

Str

ng

(---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re D

efin

e_V

aria

bles

;

begi

n Del

taE

:=

0.0

N

:= S

O;

'

uSta

r :=

1/8

6400

;

(Dim

ensi

onle

ss s

pace

in

crem

ent.

C

Nlll

i>er

of

no

des.

(1

/Del

taE

) } }

(Ref

eren

ce f

luid

vel

oci

ty.

Equ

ival

ent

to

}

07[2

8[19

95

13:5

2 F

ilen

ame:

M

ODEL

4D1.P

AS

Page

C1m

in 2

4 ho

urs.

}

Len

gth

:= 0

.5·

(Len

gth

of

the

coll.

llV'I.

(m

) }

Voi

dage

:=

0.4

2;

CV

oida

ge o

f th

e co

ll.llV

'I.

}

Ord

1

:= 1

.0;

(Rea

ctio

n or

der

of

firs

t re

acti

on

. }

Orc

l2

:= 1

.0;

(Rea

ctio

n or

der

of s

econ

d re

acti

on

. }

Orc

0

:=

1.0

; (R

eact

ion

orde

r of

th

ird

rea

ctio

n.

}

DG2

1 :=

10

.0;

(Def

ined

dim

ensi

onle

ss g

roup

. }

DG

2-2

:= 0

.0;

(Def

ined

dim

ensi

onle

ss g

roup

. }

DG

(:3

:=

0.0

; (D

efin

ed d

imen

sion

less

gro

up.

}

DG3

1 :=

1

.0;

(Def

ined

dim

ensi

onle

ss g

roup

. }

DG

r2

:= 0

.0;

(Def

ined

dim

ensi

onle

ss g

roup

. }

DG

3:J

:= 0

.0;

(Def

ined

dim

ensi

onle

ss g

roup

. }

GfM

ax_x

:=

2

.0;

CMax

iffill

ll x·

valu

e fo

r co

nver

sion

gra

ph.

} ((

Dim

ensi

onle

ss T

ime.

) }

GfM

ax_Y

:=

1

.0;

CMax

iffill

Tl y

-val

ue f

or

brea

kthr

ough

gra

ph.

} ((

Con

cent

rati

on -

kg/m

3 fl

uid

.)

}

Iter

atio

ns

= 1

00;

(Ite

rati

on

s in

tim

e.

} P

rin

tFil

ter

= 1

; CG~ p

rin

tin

g f

ilte

r.

} N

umSu

blnt

=

10;

- (

N

r of

su

bin

terv

als

wit

hin

each

sp

atia

l }

(inc

rem

ent.

}

end;

(---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re

lnit

iali

se_

Su

per

fici

al_

Vel

oci

ty_

Fil

e;

begi

n assi

gn(S

upV

elF

ile,

'Sup

Vel

Fi.

Dat

');

rese

t(S

upV

elF

ile)

; su

pVel

Dat

a[1,

1l:=

O;

SupV

elD

ata[

112J

:=O

; re

adC

Sup

Vel

F1l

e,S

upV

elD

ata[

2,1l

);

read

(Sup

Vel

Fil

e,S

upV

elQ

ata[

2,2l

);

lntl

engt

hCri

t:=

Voi

dage

*Del

taE

*Len

gth;

en

d;

(---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re T

imeO

ART

an

d SR

Ts;

(Thi

s p

roce

du

re-i

nit

iali

ses

the

alph

a an

d si

gma

vec

tors

. }

begi

n ART

[Ol

:=1;

SR

T_1

[0]

:=1;

SR

T_2[

0]

:=1;

SR

T 3[

0]

:=1;

So

lSR

T_1

[0J:

=O;

SolS

RT

2[0]

:=0;

SolSRT~ [0

] :=

O;

Hol

dSR

'r 1[

0]

=1

Hol

dSR

T-2

[OJ

=1

HoldSRT~[O]

=1

for

Arb

Tnd

ex

=1-

to N

do

begi

n

2

(j

0 Q.

-~ t-C -· Cll -· = ~

"'1 ~

0 Q.

~

~

t:; """ . ~ r:r

.i .

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13:5

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M

ODEL

4D1.P

AS

Page

3

AR

TCA

rbln

dexJ

:=O

; SR

T_1

CA

rbln

dexJ

:=1;

SR

T_2

[Arb

lnde

xJ:=

1;

SRT

_3[A

rbln

dexJ

:=1;

So

lSR

T_1C

Arb

lnde

xJ :=

O;

SolS

RT_

2CA

rbln

dexJ

:=O

; So

lSR

T 3C

Arb

lnde

xJ :=

O;

Hol

dSRT

1C

Arb

lnde

xJ

=1

Hol

dSR

T-2C

Arb

lnde

xJ

=1

Hol

dSR

T-3C

Arb

lnde

xJ

=1

end·

-

end;

'

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

-·}

Pro

cedu

re D

eter

min

e C

orre

spon

ding

Del

taT

; {T

his

proc

edur

e us

es t

he m

etho

d oT

ch

arac

teri

stic

s to

det

erm

ine

the

} {p

rogr

essi

on i

n tim

e fo

r a

give

n C

harD

elta

E.

It a

llow

s fo

r un

stea

dy

} {

stat

e fl

ow.

}

begi

n Intl

engt

h:=

O;

Del

ta t

:=O

; ·

whi

le-I

ntle

ngth

<>

lntL

engt

hCri

t do

beg

in

if E

OF(

SupV

elFi

le)

then

beg

in

clos

eseg

raph

ics;

w

rite

lnC

'ln

suff

icie

nt

Dat

a in

the

Sup

erfi

cial

V

eloc

ity

Dat

a F

ile

to')

; w

rite

ln(•

exec

ute

the

requ

ired

num

ber

of

itera

tio

ns.

');

wri

teln

('P

rese

nt

num

ber

of

iter

atio

ns:

=

1,T

imeC

ount

er);

C

ontin

ue:=

O;

Intl

eng

th:=

Intl

eng

thC

rit;

re

adln

; en

d;

Intl

engt

h:=

Intl

engt

h+C

Sup

Vel

Dat

aC2,

1J-

Sup

Vel

Dat

a[1,

1J)

*Sup

VeL

Dat

a[2,

2J;

Del

ta t

:=D

elta

t+

(Sup

Vel

Dat

a[2,

1J-

SupV

elO

ata[

1, 1

J );

If

In

tlen

gth>

Intl

engt

hCri

t th

en b

egin

A

rbV

alue

:=In

tlen

gth-

IntL

engt

hCri

t;

Del

ta t

:=D

elta

t-A

rbV

alue

/Sup

Vel

Dat

a[2,

2J;

IntL

engt

h:=

lnt[

engt

hCr1

t;

SupV

elD

ataC

1,1J

:=

Sup

Vel

Dat

a[2,

1J-A

rbV

alue

/Sup

Vel

Dat

a[2,

2l;

SupV

elD

ataC

1,2J

:=Su

pVel

Dat

aC2,

2J;

end

else

beg

in

SupV

elD

ataC

1,1J

:=Su

pVel

Dat

a[2,

1J;

SupV

elD

ataC

112J

:=S

upV

elD

ata[

2,2J

; re

ad(S

upV

elF

1le,

S

upV

elD

ata[

2,1J

);

read

CSu

pVel

File

, Su

pVel

Dat

a[2,

2J>

end;

en

Del

taT

:=D

elta

t*u

Sta

r/L

engt

h;

end;

-

{------------------------------~------------------------------------------}

Pro

cedu

re

Iter

ate

wit

hin

Del

taE

s;

{Thi

s pr

oced

ure

uPcl

ates

th

e al

pha

and

sigm

a ve

ctor

s du

ring

th

e tim

e it

{t

akes

for

th

e fl

uid

to

mov

e th

roug

h a

spat

ial

incr

emen

t.

begi

n for

Arb

lnde

x:=O

to

N d

o be

gin

for

Sub

lnte

rval

lnde

x:=

1 to

Num

Subl

nt

do b

egin

AR

TP1

CA

rbln

dexl

:=

AR

TCA

rbln

dexJ

+ O

elta

T/N

umSu

blnt

*(-O

G2_

1*A

RT

[Arb

lnde

xJ

} }

07/2

8/19

95

13:5

2 Fi

lena

me:

M

ODEL

4D1.P

AS

Page

4

SRT _

1 [A

rb In

dex]

SRT _

2 [A

rb! n

dexl

SRT_

3 [A

rbln

dexJ

ART

[Arb

lnde

xJ

end·

en

' en

d;

'

*exp

(Ord

i*l

nCSR

T 1

CA

rbln

dexJ

)))

+

Del

taT

/Num

Subl

nt*(

-DG

2 2*

AR

TCA

rbln

dexJ

*e

xp(O

rd 2

*ln(

SRT

2C

ArE

lnde

xJ))

)+

Del

tat/N

umSu

blnt

*(-D

G2

3*A

RTC

Arb

lnde

xJ

*exp

(Ord

3*l

n(SR

T_3

CA

r6In

dexJ

)));

:=

SRT

1CA

r6In

dexJ

+Oel

taT

/Num

Subl

nt*

(-DG

2 1*

DG

3 1*

AR

T[A

rbln

dexJ

*e

xpC

Ord

1*T

nCSR

T_1C

Arb

lnde

xJ>>

>;

:=SR

T 2C

ArE

inde

xJ+D

elta

T/N

umSu

blnt

* C-

DG2

2*D

G3

2*A

RTC

Arb

lnde

xJ

*exp

(Ord

2*T

nCSR

T_2

CA

rbln

dexJ

)));

:=

SRT

3CA

r6In

dexl

+Del

taT

/Num

Subl

nt*

C-DG

2 3*

DG

3 3*

AR

TCA

rbln

dexJ

*e

xp(O

rd 3

*TnC

SRT

_3C

Arb

lnde

xJ))

);

:=A

RTP1

CA

r6In

dexJ

;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re

Incr

emen

t F

luid

Vec

tors

; {T

his

proc

edur

e up

date

s tn

e al

pha

vect

or o

nce

the

flu

id h

as p

rogr

esse

d }

{thr

ough

a s

pat

ial

incr

emen

t.

}

begi

n for

Arb

lnde

x:=1

to

N d

o be

gin

SolS

RT

1CA

rbln

dexJ

:=

SolS

RT

1CA

rbln

dexJ

+(H

oldS

RT

1[

Arb

lnde

xJ-

-SR

T 1C

Arb

lnde

xJ)/

N;

-So

lSR

T 2C

Arb

lnde

xJ

:=So

lSR

T 2C

Arb

lnde

xJ+(

Hol

dSR

T

2CA

rbln

dexJ

--

SRT

2CA

rbln

dexJ

)/N

; -

SolS

RT

3CA

rbln

dexJ

:=

SolS

RT

3CA

rbln

dexJ

+(H

oldS

RT

3[A

rbln

dexJ

--

SRT

3CA

rbln

dexJ

)/N

;· -

Hol

dSRT

1[

Arb

lnde

x]

=SR

T-1

CA

rbln

dexJ

; H

oldS

RT=

2CA

rbln

dexJ

=S

RT

=2C

Arb

lnde

xJ;

1

Hol

dSRT

3C

Arb

lnde

xJ

=SRT

3C

Arb

lnde

xJ;

end;

-

-

for

Arb

lnde

x:=N

do

wnt

o 1

do b

egin

A

RTC

Arb

lnde

xJ

:=A

RT

CA

rbln

dex-

1J;

SolS

RT

1CA

rbln

dexJ

:=S

olSR

T 1C

Arb

lnde

x-1l

So

lSR

T-2

CA

rbln

dexJ

:=S

olSR

T-2

CA

rbln

dex-

1J

SolS

RT

-3C

Arb

lnde

xJ:=

SolS

RT

-3[A

rbln

dex-

1J

end;

-

-

ART

[OJ

=1

SolS

RT

1COJ

=O

So

lSR

T-2C

OJ

=O

SolS

RT-

3CO

J =O

en

d;

-

{***

**

{***

**

{***

**

{***

**

Impo

sed

boun

dary

con

d t

on.

Impo

sed

boun

dary

con

d t

on.

Impo

sed

boun

dary

con

d t

on.

Impo

sed

boun

dary

con

d t

on.

} } } }

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re U

pdat

e_B

reak

Thr

ough

Vec

tors

;

begi

n Tim

eVec

tor[

Vec

torl

ndex

J B

TCA

RTC

Vec

torln

dexJ

BT

CSRT

1C

Vec

torl

ndex

J B

TC

SRT

-2[V

ecto

rlnde

xJ

BTCSRT~CVectorlndexJ

end;

-

=Cum

Tim

e· =A

RT [N

J; I

=Sol

SRT

1

[NJ

=Sol

SR

T-2

[NJ

=Sol

SRT=

3 CN

l

Page 151: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/2

8/19

95

13:5

2 Fi

lena

me:

M

ODEL

4D1.P

AS

Page

5

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re L

abel

_Gra

ph;

begi

n Str

(N:3

,NS

);

Str

(Len

gth:

4:2,

Len

gthS

);

Str(

OG

2 1:

8:4,

0G2

1S);

St

r(O

G2

2:8:

4,D

G2

2S);

St

r(O

G2=

3:8:

4,0G

2=3S

>;

Str(

OG

3=1:

8:4,

0G3=

1S);

St

r(O

G3_

2:8:

4,0G

3_2S

);

Str

(OG

3_3:

8:4,

0G3_

3S);

G

Lab

el2:

=C

onca

t('

L '

,Len

gth

s,•

Nod

es

',NS

);

Gla

bel4

:=C

onca

t('

DG2_

1 ',O

G2_

1S,'

OG

2_2

',DG

2_2S

,' G

labe

l5:=

Con

cat(

' OG

3 1

',DG

3_1S

,' O

G3_

2 ',D

G3_

2S,'

Labe

lGra

phWi

ndow

(150

,~05

,GLa

bel2

,0,0

) L

abel

Gra

phW

indo

wC

150,

875,

GL

abel

4,0,

0)

Lab

elG

raph

Win

dow

(150

,845

,GL

abel

5,0,

0)

end;

OG

23

',DG

23S

);

OG3=

3 I ,O

G3=

3S);

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re G

raph

1_In

itia

lise

;

begi

n;

init

SE

Gra

phic

s(1f:

\tp

61);

SetC

urre

ntW

indo

w(2

);

Bor

derC

urre

ntW

indo

w(1

);

Set

Axe

sTyp

e(0,

0);

Sca

leP

lotA

rea(

0.0,

0.0,

1, 1

.2);

S

etX

Yin

terc

epts

(0.0

,0.0

);

Set

Col

or(2

);

Dra

wX

Axi

s(0.

2, 1

>;

Dra

wY

Axi

s(0.

2,1)

; L

abel

XA

xis(

1,0)

; L

abel

YA

xisC

1,0)

; T

itle

XA

xis(

'Oim

ensi

onle

ss L

engt

h');

T

itle

YA

xisC

'Dim

ensi

onle

ss C

on

cen

trat

ion

');

Titl

eWin

dow

(1M

odel

4D1'

)· L

abel

Gra

phW

indo

wC

375,

93S,

'C

once

ntra

tion

Pro

file

s',0

,0);

L

abel

_Gra

ph;

for

Arb

lnde

x:=O

to

N d

o O

atas

etX

[Arb

lnde

xl :

=A

rbln

dex*

Del

taE

; en

d;

{---

----

----

----

······

··---

----

----

----

----

······

··---

----

----

----

----

---·

} P

roce

dure

Gra

ph1_

Res

ults

;

begi

n for

Arb

lnde

x:=O

to

N d

o O

ataS

etY

[Arb

lnde

xl :=

AR

T[A

rbln

dexl

; L

ineP

lotD

ata(

Dat

aSet

X,D

ataS

etY

,N+

1,3,

0);

for

Arb

lnde

x:=O

to

N d

o D

ataS

etY

[Arb

lnde

xJ:=

SRT

1

[Arb

lnde

xl;

Lin

ePlo

tOat

aCD

ataS

etX

,Dat

aSet

Y,N

+1,

5,2)

; -

for

Arb

lnde

x:=O

to

N d

o D

ataS

etY

CA

rbln

dexl

:=SR

T 2[

Arb

inde

xl;

Lin

ePlo

tDat

a(D

ataS

etX

,Dat

aSet

Y,N

+1,

4,1)

; -

for

Arb

lnde

x:=O

to

N d

o D

ataS

etY

[Arb

inde

xl:=

SRT

3[A

rbln

dexl

; L

ineP

lotO

ata(

Dat

aSet

X,D

ataS

etY

,N+

1,7,

1);

-en

d;

{·-

-···

···-

····

····

····

-··-

····

···-

----

----

----

---·

··--

----

--·-

····

-·--

···}

P

roce

dure

Gra

ph_B

reak

Thr

ough

Cur

ves;

begi

n clos

eseg

raph

ics;

in

itse

gra

ph

ics(

'f:\

tp6

'>;

07/2

8/19

95

13:5

2 F

ilen

ame:

M

OD

EL40

1.PA

S Pa

ge

6

SetC

urre

ntW

indo

wC

2);

Bor

derC

urre

ntW

indo

w(1

);

SetA

xesT

ypeC

0,0)

; S

cale

Plo

tAre

a(0.

0,0.

0,G

fMax

_X,G

fMax

_Y);

S

etX

Yin

terc

epts

(0.0

,0.0

);

Set

Col

or(2

);

Ora

wX

Axi

s((G

fMax

X

/5),

1);

O

raw

YA

xisC

CG

fMax

-Y/5

),1);

Lab

elX

Axi

sC1,

0>;-

Lab

elY

Axi

sC1,

0);

Tit

leX

Axi

sC'D

imen

sion

less

Tim

e');

T

itle

YA

xisC

'Fra

ctio

n of

T

otal

O

rigi

nal

Con

tam

inan

t R

emov

ed');

T

itleW

indo

wC

'Mod

el40

1 '>

; L

abel

Gra

phW

indo

wC

380,

935,

'Bre

akth

roug

h C

urv

es',0

,0);

L

abel

G

raph

; fo

r A

rbln

dex:

=O

to V

ecto

rlnd

ex d

o D

ataS

etX

[Arb

lnde

xJ:=

Tim

eVec

tor[

Arb

inde

xl;

(*

for

Arb

lnde

x:=O

to

Vec

torl

ndex

do

Dat

aSet

Y[A

rbln

dexJ

:=B

TC

AR

TC

Arb

lnde

xl;

Lin

ePlo

tOat

a(O

ataS

etX

,Dat

aSet

Y,C

Vec

torl

ndex

+1)

,3,0

);

*)

for

Arb

lnde

x:=O

to

Vec

torl

ndex

do

Dat

aSet

Y[A

rbln

dexl

:=BT

CSRT

1C

Arb

lnde

x];

Lin

ePlo

tDat

a(D

ataS

etX

,Dat

aSet

Y,(

Vec

torl

ndex

+1)

,5,1

);

-fo

r A

rbin

dex:

=O.

to V

ecto

rlnd

ex d

o D

ataS

etY

CA

rbln

dexl

:=B

TC

SRT

2[

Arb

lnde

xl;

Lin

ePlo

tOat

a(D

ataS

etX

,Oat

aSet

Y,(

Vec

torl

ndex

+1)

,4,1

);

-fo

r A

rbln

dex:

=O

to V

ecto

rlnd

ex d

o D

ataS

etY

[Arb

lnde

xJ:=

BT

CSR

T

3[A

rbln

dexl

; L

ineP

lotD

ata(

Dat

aSet

X,O

ataS

etY

,(V

ecto

rlnd

ex+

1),7

,1);

-

end;

{---

----

----

----

----

----

---·

-··-

··---

--···

·---

----

----

----

--···

-····

·····-

} {M

AIN

PROG

RAM

}

begi

n

Con

tinu

e:=

1;

Cum

Tim

e :=

O;

Pri

ntF

ilte

rln

dex

:=O

; T

imec

ount

er:=

O;

Vec

torl

ndex

:=O

; T

imeV

ecto

r[V

ecto

rlnd

exJ:

=C

umT

ime;

BT

CA

RT

[Vec

torln

dexl

:=

O;

BTCS

RT_1

[V

ecto

rlnd

ex]

:=O

; BT

CSRT

2[

Vec

torl

ndex

l :=

O;

BTCS

RT=3

[V

ecto

r I n

dexl

: =

O;

Con

v 1[

Vec

torl

ndex

] :=

O;

Con

v=2

[Vec

tor I

ndex

] : =

O;

Con

v_3

[Vec

tor I

ndex

] : =

O;

Def

ine

Var

iabl

es;

Tim

eO A

RT

and

SRTs

; In

itia

lise

Su

per

fici

al V

eloc

ity

Fil

e;

Gra

ph

1_

Init

iali

se;

--

whi

le

(Con

tinu

e=1)

an

d C

Tim

eCou

nter

<It

erat

ions

) do

be

gin Tim

eCou

nter

:=T

imeC

ount

er+1

; P

rin

tFil

terl

nd

ex:=

Pri

ntF

ilte

rln

dex

+1

; O

eter

min

e_C

orre

spon

ding

_Del

taT

;

Page 152: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/2

8/19

95

13:5

2 Fi

lena

me:

M

ODEL

4D1

.PA

S Pa

ge

7

Cum

Tim

e:=C

umTi

me+

Del

taT;

It

erat

e w

ithi

n D

elta

Es;

if

Pri

ntF

ilte

rTn

dex

=P

rin

tFil

ter

then

be

gin Vec

torl

ndex

:=V

ecto

rlnd

ex+

1;

Pri

ntF

ilte

rlnd

ex:=

O;

Upd

ate_

Bre

akT

hrou

ghV

ecto

rs;

Gra

ph1

Res

ults

; en

-Inc~

emen

t F

luid

Vec

tors

; en

d;

--

read

ln(H

ardC

opy)

;. if

har

dcop

y=1

then

Scr

eenD

umpC

3,0,

2,1.

0, 1

.0,0

, 1,0

,err

or)

;

Gra

ph_B

reak

Thr

ough

Cur

ves;

re

adln

(Har

dcop

y);

if h

ardc

opy=

1 th

en S

cree

nDum

pC3,

0,2,

1.0

;1.0

,0, 1

,0,e

rro

r);

clos

eseg

raph

ics;

end.

{======================================~==================================}

Page 153: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/2

8/19

95

13:5

5 Fi

lena

me:

M

ODEL

4D2.P

AS

Page

Prog

ram

Mod

el4D

1;

{Mod

el4D

2 {

Thi

s pr

ogra

m

is a

cod

e fo

r th

e co

nvec

tive

flu

x m

odel

}

whi

ch

inco

rpor

ates

uns

tead

y st

ate

flow

. }

{ { { { {

Dea

ls w

ith v

aria

ble

so

lid

rea

ctio

n o

rder

s.

} N

ote

that

th

is c

ode

uses

the

NEW

DIM

ENSI

ONLE

SS

GROU

PS

} de

fine

d on

18

Jan

uary

199

5.

} T

his

vers

ion

pres

ents

bre

akth

roug

h cu

rves

rel

ativ

e to

so

lid

}

reac

tatn

1.

}

{Cod

ed:

Gra

ham

Dav

ies.

}

{ D

epar

tmen

t of

Che

mic

al

Eng

inee

ring

. }

<

Uni

vers

ity

of C

ape

Tow

n.

} <

19

Jan

uary

199

5.

} {

10 M

ay

1995

-

Upd

ated

. }

<===

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

==}

{Dec

lara

tion

s:

}

uses

cr

t,st

dh

dr,

gra

ph

,wo

rld

dr,

seg

rap

h,i

nte

gra

t;

var Su

pVel

File

,Exp

Dat

a

SupV

elD

ata

Dat

a

:tex

t;

:arr

ay[1

•• 2

,1 •

• 2J

of d

oubl

e;

:arr

ay[0

.. 2

56,1

.• 3

) of

dou

ble;

. ART

,ART

P1,S

RT

1,SR

T 2,

SRT

3,So

lSR

T

1,So

lSR

T

2,So

lSR

T 3

H

oldS

RT

1,H

olaS

RT

2;H

oldS

RT

3 -

--

Dat

aSet

X,D

ataS

etY

;Int

erG

1,T

nter

G 2

,lnt

erG

3

Conv

1,C

onv

2,C

onv

3 ·

--

-B

TCA

RT,

BTC

SRT_

1,B

TfSR

T_2,

BTC

SRT_

3,Ti

meV

ecto

r

lntL

eng

th,l

ntl

eng

thC

rit,

Del

ta t

,Del

taT

,Arb

Val

ue

Cun

Tim

e,E

rror

Sun

-.

DG2

1,D

G2

2,D

G2

3,D

G3

1[D

G3

2,D

G3

3,0r

d 1,

0rd

2,0r

d 3

Voiaage,Length,uStar,~e

taE

--

--

-

GfM

ax_X

,GfM

ax_Y

Arb

lnde

x,S

ubln

terv

alln

dex,

Con

tinu

e,P

rint

Fil

terl

ndex

V

ecto

rlnd

ex,H

ardC

opy,

err.

or,N

o of

D

ataP

oint

s,P

osit

ion

N,N

umS

ubln

t,It

erat

ions

,Pri

ntF

Tlt

er

No_

of _

Poi

nts

Tim

eCou

nter

NS,

Len

gthS

DG

2 1S

,DG

2_2S

(DG

2_3S

,DG

3_1S

,DG

3_2S

,DG

3_3S

G

Lao

el2,

GL

abe

4,G

Lab

el5

Sho

rtV

ecto

r;

Sho

rtV

ecto

r;

Ver

ylon

gVec

tor

Ver

ylon

gVec

tor

Ver

ylon

gVec

tor

:Dou

ble;

:D

oubl

e;

:Dou

ble;

:D

oubl

e;

:Rea

l;

Inte

ger;

In

tege

r;

Inte

ger

; In

teg

er;

:Lon

glnt

;

Str

ing

S

trin

g

Str

ing

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re D

efin

e_V

aria

bles

;

begi

n Del

taE

N

:=

0.

02;

:= 5

0;

{Dim

ensi

onle

ss s

pace

inc

rem

ent.

<N

l.lllb

er

of

node

s.

(1/D

elta

E)

} }

07/2

8/19

95

13:5

5 Fi

lena

me:

M

OOEL

4D2.P

AS

Page

2

us ta

r :=

1/

8640

0;

{Ref

eren

ce f

luid

vel

oci

ty.

Equ

ival

ent

to

} {1

m

in 2

4 ho

urs.

}

Len

gth

:= 0

.5·

{Len

gth

of

the

colu

nn.

(m)

} V

oida

ge

:= 0

.4~;

{Voi

dage

of

the

colll

ll"I.

}

Ord

1

:= 1

.0;

{Rea

ctio

n or

der

of f

irst

re

acti

on

. }

ora

2

:= 1

.0;

{Rea

ctio

n or

der

of s

econ

d re

acti

on

. }

orc:

Q

:=

1.0

; {R

eact

ion

orde

r of

th

ird

rea

ctio

n.

}

DG2

1 :=

10.

0;

{Def

ined

dim

ensi

onle

ss g

roup

. }

DG

2-2

:=

1.0

; {D

efin

ed d

imen

sion

less

gro

up.

} D

G2:

J :=

10

.0;

{Def

ined

dim

ensi

onle

ss g

roup

. }

DG3

1 :=

1

.0;

{Def

ined

dim

ensi

onle

ss g

roup

. }

DG

3-2

:=

1.0

; {D

efin

ed d

imen

sion

less

gro

up.

} D

G3:

J :=

0.0

1;

{Def

ined

dim

ensi

onle

ss g

roup

. }

GfM

ax_x

:=

4.0

; {M

axin

x.rn

x-v

alue

for

con

vers

ion

grap

h.

} {(

Dim

ensi

onle

ss T

ime.

) }

GfM

ax_Y

:=

0.0

2;

{Max

inx.

rn y

-val

ue f

or b

reak

thro

ugh

grap

h.

} {(

Con

cent

rati

on -

kg/m

3 fl

uid

.)

}

Iter

atio

ns

= 1

00;

{It

erat

ion

s in

tim

e.

} P

rin

tFil

ter

= 1

0;

{G~ p

rin

tin

g f

ilte

r.

} N

umSu

blnt

=

10;

{N

r

of s

ub

inte

rval

s w

ithi

n ea

ch s

pat

ial

} {i

ncre

men

t.

}

end;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re

lnit

iali

se_

Su

per

fici

al_

Vel

oci

ty_

Fil

e;

begi

n assi

gn(S

upV

elF

ile,

•su

pVel

Fi.

Dat

');

rese

t(S

upV

elF

ile)

; S

upV

elD

ata[

1,1J

:=O

; S

upV

elD

ata[

1,2J

:=O

; re

ad(S

upV

elF

ile,

Sup

Vel

Dat

a[2,

1J);

re

ad(S

upV

elF

ile,

Sup

Vel

Dat

a[2,

2J);

ln

tlen

gthC

rit:

=V

oida

ge*D

elta

E*L

engt

h;

end;

{---

----

----

----

----

----

·---

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re T

imeO

ART

an

d SR

Ts;

· {T

his

pro

ced

ure

-in

itia

lise

s th

e al

pha

and

sigm

a v

ecto

rs.

}

begi

n ARH

OJ

:=1;

SR

T_1

[0J:

=1;

SRT

2 [O

J :=

1;

SRT

:J [0

] : =

1;

SolS

RT

_1[0

J:=O

; So

lSR

T 2

[OJ

:=O

; SolSRT~COJ :=

O;

Hol

dSR

T 1C

OJ:

=1;

Hol

dSR

(::2[

0] :

=1;

n 0 Q.. ~

~ -· tll """" :r ~

"'S ~

0 Q.. ~ -~ ~ N . ~ 00

.

Page 154: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/2

8/19

95

13:5

5 Fi

lena

me:

M

ODEL

4D2.P

AS

Page

3

Hol

dSRT

3[0

]:=

1;

for

Arb

Tnd

ex:=

1 to

N d

o be

gin

AR

TC

Arb

inde

xl:=

O;

SRT

_1C

Arb

inde

xl:=

1;

SRT

2CA

rbin

dexJ

:=

1;

SRT~CArbindex] :

=1;

So

lSR

T_1

CA

rbin

dex]

:=O

; So

lSR

T 2C

Arb

inde

xl:=

O;

SolSRT~CArbindex] :=

O;

Hol

dSRT

1C

Arb

inde

xl:=

1;

Hol

dSR

T-2

CA

rbln

dexJ

:=1;

H

oldS

RT

=3C

Arb

inde

x]:=

1;

end;

fo

r A

rbin

dex:

=O

to m

axv

do b

egin

B

TCA

RTC

Arb

inde

xl

=O

BTCS

RT

1CA

rbin

dexl

=O

B

TCSR

T-2C

Arb

inde

xl

=O

BTC

SRT-

3CA

rbin

dexl

=O

en

d;

-en

d;

{·--

------

----

----

----

----

----

----

-~--

----

----

----

-------;·---------------}

Pro

cedu

re D

eter

min

e_C

orre

spon

ding

Del

taT

; {T

his

proc

edur

e us

es t

he m

etho

d o

r ch

arac

teri

stic

s to

det

erm

ine

rhe

} {p

rogr

essi

on i

n ti

me

for

a gi

ven

Cha

rDel

taE

. It

all

ows

for

unst

eady

}

{st

ate

flow

. }

begi

n lntl

engt

h:=

O;

Del

ta t

:=O

; w

hile

-lnt

Len

gth<

>In

tlen

gthC

rit

do

begi

n if

EO

F(Su

pVel

File

) th

en b

egin

cl

oses

egra

phic

s;

wri

teln

('In

suff

icie

nt

Dat

a in

the

Su

per

fici

al V

eloc

ity

Dat

a F

ile

to')

; w

rite

ln(•

exec

ute

the

requ

ired

num

ber

of

iter

atio

ns.

•);

·wri

teln

('P

rese

nt

num

ber

of

iter

atio

ns:

=

',Tim

eCou

nter

);

Con

tinue

:=O

; In

tlen

gth:

=ln

tlen

gthC

r1t;

re

adln

; en

lntl

engt

h:=

Intl

engt

h+(S

upV

elD

ata[

2,1J

-Sup

Vel

Dat

a[1,

1J)*

Sup

Vel

Dat

a[2,

2l;

Del

ta t

:=D

elta

t+

(Sup

Vel

Dat

aC2,

1J-S

upV

elD

ataC

1,1J

);

If

IntL

engt

h>In

tlen

gthC

rit

then

beg

in

Arb

Val

ue:=

Intl

engt

h-In

tLen

gthC

rit;

D

elta

t:=

Del

ta t

-Arb

Val

ue/S

upV

elD

ata[

2,2l

; ln

tlen

gth

:=ln

t[en

gth

Cri

t;

SupV

elD

ata[

1,1J

:=Su

pVel

Dat

a[2,

1l-

Arb

Val

ue/S

upV

elD

ata[

2,2l

; Su

pVel

Dat

a[1,

2l :

=Su

pVel

Dat

aC2,

2l;

end

else

beg

in

SupV

elD

ataC

1,1l

:=Su

pVel

Dat

aC2,

1l;

SupV

elD

ataC

112l

:=

Sup

Vel

Dat

a[2,

2l;

read

(Sup

Vel

F1l

e,

SupV

elD

ataC

2, 1

1);

read

CSu

pVel

File

, S

upV

elD

ata[

2,2l

) en

~d•

I

Del

taT

:=D

elta

_t*u

Sta

r/L

engt

h;

end;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re

Iter

ate_

wit

hin_

Del

taE

s;

07/2

8/19

95

13:5

5 F

ilen

ame:

M

ODEL

4D2.P

AS

Page

4

{Thi

s pr

oced

ure

upda

tes

the

alph

a an

d si

gma

vect

ors

duri

ng t

he

tim

e it

{t

akes

for

th

e fl

uid

to

mov

e th

roug

h a

spat

ial

incr

emen

t.

begi

n for

Arb

lnde

x:=O

to

N d

o be

gin

for

Sub

lnte

rval

lnde

x:=

1 to

Num

Subl

nt

do

begi

n A

RT

P1[A

rb!n

dex]

:=

AR

T[A

rbln

dex]

+ D

elta

T/N

umSu

blnt

*(-D

G2

1*A

RT

[Arb

lnde

xl

*exp

(Ord

1*l

n(SR

T

1CA

r6In

dex]

)))+

D

elta

T/N

umSu

blnt

*(-D

G2

2*A

RTC

Arb

lnde

xl

*exp

(Ord

2*l

n(SR

T

2CA

r6In

dex]

)))+

D

elta

T/N

Lim

Subl

nt*(

·DG

2 3*

AR

TCA

rbln

dex]

*e

xpC

Ord

3*l

nCSR

T_3

CA

roln

dexJ

)));

SR

T 1[

Arb

lnde

x]

:=SR

T 1C

Ar6

Inde

xl+D

elta

T/N

umSu

blnt

* -

(·DG

2 1*

DG

3 1*

AR

T[A

rbln

dexl

*e

xp(O

rd 1

*TnC

SRT

_1C

Arb

lnde

x]))

);

SRT

2[A

rbln

dex]

:=

SRT

2CA

r61n

dexJ

+Del

taT

/Num

Subl

nt*

-(-D

G2

2*D

G3

2*A

RT

[Arb

lnde

x]

*exp

(Ord

2*T

nCSR

T 2C

Arb

lnde

xJ))

);

SRT

3[A

rbln

dex]

:=

SRT

3[A

r6In

dex]

+Del

taT

/Nl.l

llSU

blnt

* -

(·DG

2 3*

DG

3 3*

AR

TCA

rbln

dex]

ART

[Arb

lnde

xl

end·

en

'

*exp

(Ord

3*T

nCSR

T 3C

Arb

inde

x]))

);

:=A

RT

P1C

Ar6

Inde

xl;

-

end;

'

} }

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re

Incr

emen

t F

luid

Vec

tors

; {T

his

proc

edur

e up

date

s tn

e al

pha

vec

tor

once

the

flu

id h

as

prog

ress

ed

} {t

hrou

gh a

sp

atia

l in

crem

ent.

}

begi

n for

Arb

lnde

x:=1

to

N d

o be

gin

1

SolS

RT

1[A

rb!n

dex]

:=

SolS

RT

1CA

rbin

dex]

+(H

oldS

RT

1

[Arb

lnde

x]-

-SR

T 1C

Arb

lnde

x])/

N;

-So

lSR

T 2C

Arb

lnde

x]

:=So

lSR

T 2C

Arb

lnde

x]+(

Hol

dSR

T

2[A

rbln

dex]

--

SRT

2CA

rbln

dex]

)/N

; -

SolS

RT

3CA

rbln

dexl

:=

SolS

RT

3CA

rbln

dexJ

+(H

oldS

RT

3[A

rbin

dexJ

--

SRT

_3C

Arb

inde

xJ)/

N;

-H

oldS

RT

1[A

rbln

dexl

=S

RT

1CA

rbln

dexl

; H

oldS

RT

=2[A

rbln

dex]

=S

RT

=2[A

rbln

dexl

; H

oldS

RT

_3[A

rbln

dex]

=S

RT

_3[A

rbln

dexl

; en

d;

for

Arb

lnde

x:=N

do

wnt

o 1

do b

egin

A

RTC

Arb

lnde

xl

:=A

RT

[Arb

!nde

x-1]

; So

lSR

T 1C

Arb

lnde

xJ:=

SolS

RT

1C

Arb

inde

x-1J

So

lSR

T-2

[Arb

lnde

xl :

=Sol

SRT

-2C

Arb

inde

x-1J

So

lSR

T-3

[Arb

inde

x]:=

SolS

RT

-3C

Arb

lnde

x-1J

~d;

--

ARTC

OJ

=1

Sol S

RT

1 [0

] =O

So

lSR

C2C

0l

=O

Sol

SR

C3[

0]

=0 .

en

d;

-

{***

**

<***

**

{***

**

{***

**

Impo

sed

boun

dary

con

dit

on.

l~sed

boun

dary

con

dit

on.

Impo

sed

boun

dary

con

dit

on.

Impo

sed

boun

dary

con

dit

on.

} } } }

{~--

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re U

pdat

e_B

reak

Thr

ough

Vec

tors

;

Page 155: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/2

8/19

95

13:5

5 Fi

lena

me:

M

ODEL

4D2.P

AS

Page

5

begi

n Tim

eVec

tor[

Vec

torl

ndex

l =C

umTi

me;

B

TC

AR

T[V

ecto

rlnde

x]

=ART

[NJ;

BTCS

RT

1[V

ecto

rlnd

exJ

=Sol

SRT

1[N

l;

if D

G3-

2<>0

th

en B

TCSR

T 2[

Vec

torl

ndex

l if

DG3~<>0

then

BT

CSR

T-3

[Vec

torln

dexJ

en

d;

-

:=So

lSR

T_2C

Nl*

DG

3_1/

DG

3_2;

:=

SolS

RT

_3[N

l*D

G3_

1/D

G3_

3;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re L

abel

_Gra

ph;

begi

n Str

(N:3

,NS

);

Str

(Len

gth:

4:2,

Len

gthS

);

Str(

DG

2 1:

8:4,

DG

2_1S

);

Str(

DG

2_2:

8:4,

DG

2_2S

);

Str(DG2~:8:4,DG2

3S);

St

r(D

G3

1:8:

4,D

G3

1S);

St

r(D

G3=

2:8:

4,D

G3=

2S);

St

r(D

G3=

3:8:

4,D

G3=

3S);

G

Lab

el2:

=C

onca

t('

L '

,Len

gth

s,'

Nod

es

',NS

);

GL

abel

4:=

Con

cat(

' DG

2_1

',DG

2_1S

,' D

G2_

2 ',D

G2_

2S,'

GL

abel

5:=

Con

cat(

' DG

3 1

',DG

3_1S

,' D

G3_

2 ',D

G3_

2s,'

Lab

elG

raph

Yin

dow

C15

0,90

5,G

Lab

el2,

0,0)

L

abel

Gra

phY

indo

w(1

50,8

75,G

Lab

el4,

0,0)

L

abel

Gra

phY

indo

w(1

50,8

45,G

Lab

el5,

0,0)

en

d;

DG2

3 ',D

G2

3S);

OG

3=3

I ,D

G3=

3S);

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re G

raph

1_1n

itia

lise

;

begi

n;

in1t

SE

Gra

phic

s('f

:\tp

61);

Set

Cur

rent

Yin

dow

(2);

B

orde

rCur

rent

Yin

dow

(1);

S

etA

xesT

ype(

0,0)

· S

cale

Plo

tAre

a(0.

0,0.

0, 1

, 1.2

>;

Set

XY

lnte

rcep

ts(0

.0,0

.0);

S

etC

olor

(2);

D

raw

XA

xis(

0.2,

1);

Dra

wY

Axi

s(o.

2 61);

L

abel

XA

xis(

1,

>;

Lab

elY

Axi

s(1,

0);

Tit

leX

Axi

sC'D

imen

sion

less

Len

gth'

);

Tit

leY

Axi

s('D

imen

sion

less

Co

nce

ntr

atio

n')

; T

itleY

indo

wC

'Mod

el4D

2');

L

abel

Gra

phY

indo

w(3

75,9

35,

'Con

cent

rati

on P

rofi

les'

,0,0

);

Lab

el_G

raph

; fo

r A

rbln

dex:

=O

to N

do

Dat

aSet

X[A

rbln

dexJ

:=A

rbln

dex*

Del

taE

; en

d; _

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re G

raph

1_R

esul

ts;

begi

n for

Arb

lnde

x:=O

to

N d

o D

ataS

etY

CA

rbln

dexJ

:=A

RT

CA

rbln

dexJ

; L

ineP

lotD

ata(

Dat

aSet

X,D

ataS

etY

,N+

1,3,

0);

for

Arb

lnde

x:=O

to

N d

o D

ataS

etY

CA

rbln

dexJ

:=S

RT

1CA

rbln

dexJ

; L

ineP

lotD

ata(

Dat

aSet

X,D

ataS

etY

,N+

1,5,

2);

-fo

r A

rbln

dex:

=O

to N

do

Dat

aSet

YC

Arb

lnde

xJ :=

SRT

2CA

rbln

dexJ

; L

ineP

lotD

ata(

Dat

aSet

X,D

ataS

etY

,N+

1,4,

1);

.-

for,

Arb

lnde

x:=

O

to N

do

Dat

aSet

YC

Arb

lnde

xJ :=

SRT

3CA

rbln

dexJ

; L

ineP

lotD

ata(

Dat

aSet

X,D

ataS

etY

,N+

1,7,

1);

-

. ------------

-

07/2

8/19

95

13:5

5 F

ilen

ame:

M

OD

EL4D

2.PA

S Pa

ge

6

end;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re G

raph

_Bre

akT

hrou

ghC

urve

s;

begi

n clo

sese

gra

ph

ics;

in

itse

gra

ph

ics(

1f:

\tp

6')

; S

etC

urre

ntY

indo

w(2

);

Bor

derc

urre

ntY

indo

w(1

);

SetA

xesT

ypeC

0,0)

; S

cale

Plo

tAre

a(0.

0,0.

0,G

fMax

_X,G

fMax

_Y);

S

etX

Yln

terc

epts

(0.0

,0.0

);

Set

Col

or(2

);

Dra

wX

Axi

sCC

GfM

ax

X/5

),1

);

Dra

wY

Axi

sCC

GfM

ax-Y

/5),1

); L

abel

XA

xis(

1,0)

;-L

abel

YA

xisC

1,0>

; T

itle

XA

xisC

'Dim

ensi

onle

ss T

ime'

);

Tit

leY

Axi

s('B

reak

thro

ugh

Con

e.

Rel

. to

Ori

gina

l Q

uant

ity

Sol

. 1

.');

T

itleY

indo

w('M

odel

4D2

');

' L

abel

Gra

phY

indo

w(3

80,9

35,'B

reak

thro

ugh

Cu

rves

',0,0

);

Lab

el

Gra

ph;

· fo

r A

rbln

dex:

=O

to V

ecto

rlnd

ex d

o D

ataS

etX

CA

rbln

dexJ

:=

Tim

eVec

tor[

Arb

!nde

xl;

(*

for

Arb

lnde

x:=O

to

Vec

torl

ndex

do

Dat

aSet

YC

Arb

!nde

xJ :

=BTC

AR

TCA

rb!n

dexJ

; L

ineP

lotD

ata(

Dat

aSet

X,D

ataS

etY

,(V

ecto

rlnd

ex+

1),3

,0);

*)

fo

r A

rbln

dex:

=O

to V

ecto

rlnd

ex d

o D

ataS

etY

CA

rbln

dexJ

:=B

TC

SRT

1[

Arb

lnde

xJ;

Lin

ePlo

tDat

a(O

ataS

etX

,Dat

aSet

Y,(

Vec

torl

ndex

+1)

,5, 1

);

-.

for

Arb

lnde

x:=O

to

Vec

torl

ndex

do

Dat

aSet

Y[A

rbln

dexJ

:=BT

CSRT

2C

Arb

lnde

xJ;

Lin

ePlo

tDat

a(D

ataS

etX

,Dat

aSet

Y,C

Vec

torl

ndex

+1)

,4, 1

);

-fo

r A

rbln

dex:

=O

to V

ecto

rlnd

ex d

o D

ataS

etY

CA

rbln

dexJ

:=B

TC

SRT

3C

Arb

lnde

xJ;

Lin

ePlo

tDat

a(D

ataS

etX

,Dat

aSet

Y,(

Vec

torl

ndex

+1)

,7,1

);

-

end;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

{MAI

N PR

OGRA

M

)

begi

n

Con

tinu

e:=

1;

Cum

Tim

e :=

O;

Pri

ntF

ilte

rln

dex

:=O

; T

imeC

ount

er:=

O;

Vec

torl

ndex

:=O

; T

imeV

ecto

r[V

ecto

rlnd

exJ:

=C

umT

ime;

BT

CA

RT

[Vec

torln

dexJ

:=

O;

BTCS

RT_1

[V

ecto

rlnd

exJ

:=O

; BT

CSRT

_2 [

Vec

tor I

ndex

] :=

O;

BT

CSR

T_3

[Vec

torln

dex]

:=

0;

Con

v 1[

Vec

torl

ndex

J :=

O;

Con

v-2C

Vec

torl

ndex

J :=

O;

Con

v:3c

Vec

torl

ndex

J :=

0;

Def

ine

Var

iabl

es;

Tim

eO A

RT

and

SRTs

; In

itia

lise

su

per

fici

al V

eloc

ity

Fil

e;

Gra

ph

1_

1n

itia

lise

; -

-

Page 156: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/2

8/19

95

13:5

5 Fi

lena

me:

M

ODEL

4D2.P

AS

Page

7

whi

le

(Con

tinu

e=1)

an

d (T

imeC

ount

er<

lter

atio

ns)

do

begi

n Tim

eCou

nter

:=T

imeC

ount

er+1

; P

rin

tFil

terl

nd

ex:=

Pri

ntF

ilte

rln

dex

+1

; D

eter

min

e C

orre

spon

ding

Del

taT

; CumTime:=~umTime+DeltaTT

Iter

ate

wit

hin

Del

taE

s;

if P

rin

tFil

terT

nd

ex=

Pri

ntF

ilte

r th

en

begi

n Vec

torl

ndex

:=V

ecto

rlnd

ex+

1;

Pri

ntf

ilte

rln

dex

:=O

; U

pdat

e_B

reak

Thr

ough

Vec

tors

; G

raph

1_R

esul

ts;

en

lnc~ement

Flu

id V

ecto

rs;

end;

-

-

read

ln(H

ardC

opy)

; if

har

dcop

y=1

then

Scr

eenD

ump(

3,0,

2, 1

.0, 1

.0,0

, 1,0

,err

or)

;

Gra

ph_B

reak

lhro

ughC

urve

s;

read

ln(H

ardc

opy)

; if

har

dcop

y=1

then

Scr

eenD

umpC

3,0,

2, 1

.0, 1

.0,0

, 1-,

0,er

ror)

;

clos

eseg

raph

ics;

end.

{=

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

}

Page 157: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

Appendix ID. Solution Algorithm and Code for Model2D.PAS.

Model2 essentially represents suitable computer routines for Dixon's [1992] particle scale model discussed in Chaper 4.

Solution Algorithm for Model2D.

Start. I Set/I nitialis.e Variables.

Iterate in Time.

Calculate the A-Matrix and Y-Vector required for the Crank-Nicolson Method.

l Use the A-Matrix and Y-Vector to calculate the Alpha and Sigma vectors within the Particle.

I Graph profiles.

I

I Graph conversion versus time.

End.

Page 158: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

0/19

95

15:Q

1 Fi

lena

me:

M

ODEL

2D2.P

AS

-----~--

P;ig

e

Prog

ram

Mod

el2D

2; ·

{Mod

el2D

2.

{ T

his

prog

ram

cal

cula

tes

the

con

cen

trat

ion

pro

file

of

flu

id

} an

d so

lid

rea

ctan

ts w

ithi

n a

par

ticl

e us

ing

the

equa

tion

s as}

{ { { { { { { { { { { { { { { { {

deve

lope

d by

Dix

on.

} In

clud

es t

he p

oss

ibil

ity

of

a se

cond

so

lid

rea

ctan

t.

} In

clud

es t

he p

oss

ibil

ity

of·

a s

urf

ace

conc

entr

atio

n }

dif

fere

nt

to t

he b

ulk

con

cen

trat

ion

. }

Allo

ws

for

a· r

eact

ion

ord

er

in t

erm

s of

th

e so

lid

.rea

ctan

t }

othe

r th

an 1

. }

Thi

s pr

ogra

m a

lso

cal

cula

tes

the

frac

tio

nal

co

nver

sion

. }

Num

eric

al

stra

teg

y u

sed

is a

for

m o

f C

rank

-Nic

olso

n Im

pli

cit

}

fin

ite d

iffe

ren

ce.

}

Ass

umpt

ions

in

th

is m

odel

in

clud

e:

} Th

e so

lid

rea

ctan

t d

epo

sits

wit

hin

the

par

ticl

e }

rese

mbl

e th

ose

on

the

surf

ace.

}

The

dep

osi

ts w

ould

bot

h re

act

to t

he s

ame

exte

nt

} if

eac

h w

ere

expo

sed

to t

he s

ame

acid

co

nce

ntr

atio

n

} fo

r th

e sa

me

tim

e.

} S

urfa

ce a

cid

co

nce

ntr

atio

n i

s sti

ll

assu

med

to

be

} co

nsta

nt

-ie

alw

ays

1.

}

{Cod

ed:

Gra

ham

Dav

ies.

}

<

Dep

artm

ent

of

Che

mic

al

Eng

inee

ring

. }

{ U

nive

rsit

y of

C

ape

Tow

n.

} <

5

Aug

ust

1994

. }

{ 28

Ju

ly

1995

-

Upd

ated

. }

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

{Dec

lara

tion

s:

}

uses

crt

,std

hdr,

gj,g

raph

,wor

lddr

,seg

raph

,int

egra

t,M

2C1B

rent

Roo

ts;

cans

t Bet

a1

=1.

0;

Kap

paP1

=

10.0

;

Lam

bda1

=

0.0;

Ord

SP1

=1.

0;

Bet

a2

=0.

0;

Ka~P2

=0.

0;

La

a2

=0.

0;

Ord

SP2

=O.O

;

N

=24;

Del

taT

=

0.00

05;

Del

taE

=1

/CN

+1);

Nor

m_C

rit

=1e

-10;

Con

v_C

rit ~1

e-8;

sc

one

Tol

=1e

-5·

-,

{Dim

ensi

onle

ss S

toic

hiom

etri

c ra

tio

def

ined

pg

11

} {R

atio

of

reat

ion

rat

e of

so

lid

rea

ctan

t re

sid

ing

}

{wit

hin

the

par

ticl

e to

por

ous

dif

fusi

on

of

flu

id

} {i

nto

the

par

ticl

e.

Def

ined

pg

11

Dix

on.

} {

frac

tio

n o

f th

e te

acha

ble

mat

eria

l on

th

e su

rfac

e.}

{Lam

bda1

=1

impl

ies

all

th

e m

ater

ial

is o

n th

e }

{su

rfac

e.

} {R

eact

ion

orde

r of

th

e so

lid

in

the

por

es.

}

{Hal

f th

e nu

mbe

r of

in

teri

or

po

ints

. r=

O

and

r=R

} {n

ot

incl

uded

. }

{Tim

e In

crem

ent

} {S

pace

In

crem

ent.

C

alcu

late

d fr

om

1/(N

+1)

. (S

ince

}

<

R=i

*dE

and

R i

s at

poi

nt N

+1.)

} {C

onve

rgen

ce c

rite

ria b

ased

on

the

norm

of

vec

tor

} {*

**

} {C

onve

rgen

ce c

rite

ria f

or

the

Bre

nt

Rou

tine

. }

<D

imen

sion

less

con

cent

rati

on o

f so

lid

bel

ow

whi

ch

} {

it

is a

ssum

ed

to b

e n

egli

gib

le.

}

07/3

0/19

95

15:0

1 F

ilen

ame:

M

OD

EL2D

2.PA

S Pa

ge

2

var M

axlt

er

=100

;

lter

atio

ns=

60

0;

Pri

nt

Cri

t=10

; G

f2_M

axX

=3

0;

<Max

imum

it

erat

ion

s fo

r th

e B

rent

R

outi

ne.

{It

erat

ion

s in

tim

e.

{Det

erm

ined

fro

m d

esir

ed P

rin

t D

elta

T/D

elta

T

{Gra

ph

2 m

axim

um d

imen

sio

nle

ss-r

eact

ion

time~

AR

T,A

RTP

1,SR

T1,S

RT1

P1,S

RT1

P1C

SR

T2,

SRT

2P1,

SRT

2P1C

,YV

ecto

r D

ataS

etX

,Dat

aSet

Y,l

nter

G1,

lnte

rG2

Con

v1,C

onv2

A

Mat

rix,

Aln

vers

e A

Mat

Det

,lnte

gVal

,XA

xisM

ax

Nor

m1,

Nor

m2,

A,A

P1,S

,Roo

t,Val

ueA

tRoo

t

Row

s,C

ols,

Arb

lnde

x,D

ataP

oint

s,R

epea

ts

erro

r,P

lot

Var

,Con

v V

ar,N

ewtl

ters

H

ardC

opy1

,Har

dCop

y2-

Bet

a1S,

Kap

paP1

S,la

mbd

a1S,

GD

TS,

GL

abel

1 B

eta2

S,K

appa

P2S,

Lam

bda2

S,G

Lab

el2

Ord

SP1S

,Ord

SP2S

{ART

A

lpha

fn

(r)

at

tim

e T

CA

RTP1

A

lpha

fn

(r)

at

tim

e T+

1 {S

RT1

Sigm

a fn

(r)

at

tim

e T

(S

RTs

P1

Sigm

a fn

(r)

at

tim

e T+

1 {S

RTs

P1C

Si

gma

fn(r

) at

ti

me

T+1

·sh

ort

Vec

tor;

"S

hort

Vec

tor;

·v

eryl

ongV

ecto

r;

·ver

yLon

gVec

tor;

·s

qrM

at;

real

; re

al;

inte

ger

; in

teg

er;

inte

ger

;

str

ng

str

ng

str

ng

(gue

ssed

) (c

alcu

late

d)

rang

e 0 .

. N

rang

e 0 .

. N

rang

e 0 .

. N

rang

e 0 .

. N

rang

e 0 .

. N

{YV

ect

'Con

st'

vec

tor

in C

rank

-Nic

olso

n m

etho

d ra

nge

0 .. N

C

AM

atrix

M

atri

x of

Cra

nk-N

icol

son

coef

ftci

ents

ra

nge

N*

N

{Dat

aSet

X

X v

ecto

r us

ed

in t

he g

raph

ing

r9u

tin

e ra

nge

0 .. N

+1

} } } } } } } } } } } }

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Fun

ctio

n P

ower

(Bas

e,P

ow:r

eal)

:Ext

ende

d;

begi

n if P

ow=O

th

en P

ower

:=1

else

if

Bas

e=O

th

en P

ower

:=O

el

se

Pow

er:=

exp(

Pow

*ln(

base

));

end;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re T

imeO

AR

T an

d SR

Ts;

{Thi

s pr

oced

ure-

uses

th

e in

itia

l co

nd

itio

ns

to s

et t

he

alph

a an

d si

gma

{vec

tors

. } }

surf

ace}

{N

ote

that

ART

[N

+1J,

ARTP

1 tN

+1l,

SRT1

[N

+1J

and

SRT1

P1 [

N+1

J ar

e th

e {c

on

cen

trat

ion

s of

th

e li

qu

id a

nd s

oli

d r

eact

ants

. be

gin fo

r A

rbln

dex:

=O

to N

do

begi

n A

RT

"[A

rbln

dexJ

:=O

; SR

T1"

CA

rbln

dexJ

:=1;

SR

T2"

[Arb

lnde

xJ:=

1;

end;

A

RT. [

N+1

J :=

1;

SRT1

. [N

+1J

:=1;

}

n 0 c..

~

t""4 -· Cl'.> !'

"to,

-· :s ~

""S :: 0 c..

~ N ~

N . ~ 00

.

Page 159: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

0/19

95

15:0

1 F

ilen

ame:

M

OD

EL2D

2.PA

S Pa

ge

3

• SR

T2"

[N+1

J:=1

; A

RTP1

. [N

+ll

:=1;

(I

mpo

sed

boun

dary

con

diti

on o

f th

e co

nce

ntr

atio

n o

f (t

he

bulk

flu

id

rem

aini

ng c

onst

ant

to t

he o

rig

inal

(v

alu

e.

if K

appa

P2=0

th

en f

or A

rbln

dex:

=O

to m

axc

do

begi

n SRT2

" [A

rbln

dexJ

=O

SR

T2P1

. [A

rbln

dexJ

=O

SR

T2P1

C. [

Arb

lnde

xJ

=O

end·

en

d;

'

} } }

(---

-. --

----

---

----

-----

----

----

----

·; --

----

----

----

----

----

----

----

----

--}

Pro

cedu

re G

uess

SR

TsP

l; {T

his

proc

edur

e-pr

ovid

es t

he in

itia

l "g

uess

" fo

r th

e it

era

tio

n.

It u

ses

} (t

he

prev

ious

tim

e in

terv

al's

val

ues

as

the

gues

s.

} be

gin fo

r A

rbln

dex:

=O

to C

N+1

) do

be

gin

SRT

1P1"

[Arb

lnde

xl:=

SRT

1"[A

rbln

dexJ

; SR

T2P

1"(A

rbin

dex]

:=SR

T2"

[Arb

lnde

xJ;

end·

en

d;

'

{--

----

----

--·-

----

----

----

---·

-·--

----

·---

----

----

----

----

----

----

--·-

---}

P

roce

dure

ReG

uess

SR

TsP1

; {T

his

proc

edur

e pr

ovid

es a

n up

date

d "g

uess

" fo

r th

e ne

xt

itera

tio

n.

It

{use

s th

e SR

T1P1

C ve

ctor

as

the

upda

ted

gues

s.

begi

n for

Arb

lnde

x:=O

to

CN

+1)

do

begi

n SR

T1P1

" [A

rbln

dex]

:=S

RT

1P1C

"[A

rbln

dexJ

; SR

T2P

1"[A

rbln

dexJ

:=SR

T2P

1C"[

Arb

lnde

xl;

end·

en

d;

'

} }

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re C

ale

AM

atri

x an

d Y

vec

tor·

{T

his

proc

edur

e ca

lcu

late

s-tn

e C

rank

-Nic

olso

n co

effi

cien

t m

atri

x.

} be

gin fo

r R

ows:=

O

to (

N+1

) do

be

gin fo

r C

ols:

=O

to (

N+1

) do

A

Mat

rix·

[R

ows,

Col

sJ :

=O;

end;

AM

atri

x"[0

,0J:

=·6

·Del

taE

*Del

taE

*CK

appa

P1*

Pow

er(S

RT

1P1"

[0J

,Ord

SP1)

+K

appa

P2*P

ower

CSR

T2P

1"[0

],0rd

SP2)

) -2

*Del

taE

*Del

taE

/Del

taT

; A

Mat

rix"

CO,

1)

:=6;

Y

Vec

tor"

[OJ

:=A

RT

"[0J

*C6+

Del

taE

*Del

taE

*CK

appa

P1*P

ower

(SR

T1.

[0J,

Ord

SP1)

+K

appa

P2*P

ower

(SR

T2"

[0J,

Ord

SP2)

) ·2

*Del

taE

*Del

taE

/Del

taT

)·A

RT

.[1]

*6;

07/3

0/19

95

15:0

1 F

ilen

ame:

M

OD

EL2D

2.PA

S Pa

ge

4

for

Row

s:=1

to

N-1

do

be

gin AM

atr i

[Row

s, R

ows-

11 :

=R

ows-

1;

AM

atri

x-[R

ows,

Row

sl

:=-2

*Row

s-R

ows*

Del

taE

*Del

taE

*(

Kap

paP1

*Pow

er(S

RT

1P1"

[Row

s],O

rdSP

1)+

Kap

paP2

*Pow

er(S

RT

2P1"

[Row

sJ,O

rdSP

2))

-2*R

ows*

Del

taE

*Del

taE

/Del

taT

; A

Mat

rix"

[Row

s,R

ows+

1J:=

Row

s+1;

Y

Vec

tor"

[Row

sJ

:=A

RT

"[R

ows·

1J*C

·Row

s+1)

+AR

T"[

Row

sl*C

2*R

ows+

Row

s*

end;

Del

taE

*Del

taE

*C

Kap

paP1

*Pow

er(S

RT

1"[R

owsJ

,Ord

SP1)

+K

appa

P2*P

ower

CSR

T2"

CR

owsJ

,Ord

SP2)

) -2

*Row

s*D

elta

E*D

elta

E/D

elta

T)

+AR

T"[

Row

s+1]

*(·R

ows-

1);

AM a

t r ix

. [N

, N

-11

: =N

-1;

AM

atri

x"(N

,NJ

:=·2

*N-N

*Del

taE

*Del

taE

*(K

appa

P1*P

ower

(SR

T1P

1" [

NJ,

Ord

SP1)

+K

appa

P2*P

ower

(SR

T2P

1"[N

],Ord

SP2)

) ·2

*N*D

elta

E*D

elta

E/D

elta

T;

YV

ecto

r"[N

J :=

AR

T"[

N-1

l*C

·N+1

)+A

RT

"[N

J*C

2*N

+N*D

elta

E*D

elta

E*

(Kap

paP1

*Pow

er(S

RT

1"[N

],O

rdSP

1)

+Kap

paP2

*Pow

er(S

RT

2"[N

J,O

rdSP

2))

-2*N

*Del

taE

*Del

taE

/Del

taT

)+

AR

T"[

N+1

J*C

-N-1

)·AR

TP1

"[N

+1]*

(N+1

);

end;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re C

alcS

RT

sP1C

; {T

his

proc

edur

e is

a n

on

-lin

ear

root

fi

nd

ing

pro

cedu

re.

It

uses

Bre

nt'

s }

(Met

hod

to s

olv

e fo

r th

e ro

ot.

}

begi

n if

X]

ex]

(Kap

paP1

<>0)

th

en b

egin

if

Ord

SP1=

1 th

en b

egin

end SR

T1P

1C"[

Arb

lnde

x] :

=SR

T1"

[Arb

lnde

xl*C

1-D

elta

T*K

appa

P1*B

eta1

*AR

T.[

Arb

lnde

/C2*

C1-

Lam

bda1

)))/

(1+

Del

taT

*Kap

paP

1*B

eta1

* A

RT

P1"[

Arb

lnde

xJ/C

2*C

1-L

ambd

a1))

);

else

if

SR

T1P

1"[A

rbln

dexl

<SC

onc_

Tol

th

en S

RT

1P1C

"[A

rbln

dex]

:=S

RT

1P1.

CA

rbln

d

else

beg

in

A

:=A

RT

"[A

rbln

dexl

; A

P1:=

AR

TP1

"[A

rbln

dexJ

; s

:=SR

T1"

CA

rbln

dexJ

; S

RT

1P1C

"[A

rb!n

dexJ

:=B

rent

Roo

ts(0

.0,1

.0,D

elta

T,K

appa

P1,

Bet

a1,L

ambd

a1,0

rdS

P1

,A,A

P1,

X]

S, 1

e-8,

100,

Val

ueA

tRoo

t,er

ror)

; en

end·

'

if

CK

appa

P2<>

0)

then

beg

in

if O

rdSP

2=1

then

beg

in

SRT

2P1C

"[A

rb!n

dexJ

:=SR

T2"

[Arb

lnde

x]*(

1-D

elta

T*K

appa

P2*B

eta2

*AR

T"[

Arb

lnde

/C2*

C1·

Lam

bda2

)))/

(1+

0elt

aT*K

appa

P2*

Bet

a2*

AR

TP1

"[A

rbln

dexl

/C2*

C1-

Lam

bda2

)));

Page 160: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

0/19

95

15:0

1 F

ilen

ame:

M

ODEL

2D2.P

AS

Page

5

ex]

end

else

if

SRT

2P1"

[Arb

lnde

xJ<S

Con

c_T

ol

then

SR

T2P1

c· [

Arb

lnde

xl :

=SR

T2P

1"[A

rbln

d

else

beg

in

A

:=A

RT"

[Arb

lnde

xl;

AP1

:=A

RT

P1"[

Arb

lnde

xJ;

s :=

SRT

2"[A

rbln

dexl

; SR

T2P

1C"[

Arb

lnde

xl :

=B

rent

Roo

ts(O

.O, 1

.0,D

elta

T,K

appa

P2,

Bet

a2,L

ambd

a2,0

rdS

P2

,A,A

P1,

end·

en

' en

d;

'

S, 1

e-8,

100

,Val

ueA

tRoo

t,er

ror)

;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re C

heck

C

onve

rgen

ce;

{Thi

s pr

oced

ure-

chec

ks w

heth

er

or n

ot

the

solu

tio

n h

as

conv

erge

d by

}

{com

pari

ng t

he g

uess

ed v

alue

of

SRT1

P1

with

a

calc

ula

ted

val

ue o

f SR

T1P1

. }

begi

n Nor

m1:

=0;

{Usi

ng

a no

rm**

* }

Nor

m2:

=0;

for

Arb

lnde

x:=O

to

CN

+1)

do

begi

n C

alcS

RTs

P1C

; if

(B

eta1

<>0)

an

a C

Kap

paP1

<>0)

th

en b

egin

N

orm

1:=C

SRT

1P1C

"[A

rbln

dex]

-SR

T1P

1"[A

rbln

dexJ

)*(S

RT

1P1C

"[A

rbln

dexJ

­SR

T1P

1"[A

rbln

dexl

);

end

else

Nor

m1:

=0;

if

(Bet

a2<>

0)

and

CK

appa

P2<>

0)

then

beg

in

Nor

m2:

=(SR

T2P

1C"[

Arb

lnde

x]-S

RT

2P1"

[Arb

lnde

x])*

(SR

T2P

1C"[

Arb

lnde

x]­

SRT

2P1"

[Arb

lnde

x] )

; en

d el

se N

orm

2:=0

; en

end;

'

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re U

pdat

e AR

T an

d SR

Ts;

{Thi

s pr

oced

ure

upda

tes

the

alph

a an

d si

gma

vect

ors

for

the

next

it

erat

ion

}

Cby

repl

acin

g th

eir

com

pone

nts

wit

h th

e al

phaT

+1

and

sigm

aT+1

v

ecto

rs.

} be

gin fo

r A

rbln

dex:

=O

to (

N+1

) do

be

gin

AR

T"[

Arb

lnde

xl :

=AR

TP1

"[A

rbin

dexl

; SR

T1"

[Arb

lnde

xJ:=

SRT

1P1"

[Arb

inde

xl;

SRT

2"[A

rbln

dexl

:=

SRT

2P1"

[Arb

lnde

xl;

end·

en

d;

'

{---

----

----

----

----

----

----

·---

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re C

ale

Con

vers

ion;

{T

his

procedur~ ca

lcu

late

s th

e fr

acti

on

al

conv

ersi

on o

f th

e p

art

icle

fo

r }

{th

e ti

me

inte

rval

. It

use

s th

e fo

rmul

a on

pg

. 13

Dix

on.

The

inte

gra

tor

} {

is t

he Q

uinn

-Cur

tis

vect

or

inte

gra

tor.

}

begi

n

07/3

0/19

95

15:0

1 F

ilen

ame:

M

OD

EL2D

2.PA

S Pa

ge

6

if K

appa

P1<>

0 th

en b

egin

fo

r A

rbln

dex:

=O

to C

N+1

) do

ln

terG

1"[A

rbln

dexJ

:=

C1-

SR

T1"

[Arb

lnde

xJ)*

Arb

lnde

x*D

elta

E*A

rbln

dex*

Del

taE

;

lnte

grat

eVec

torC

lnte

rG1"

,Del

taE

,0,(

N+

1)

Inte

gVal

);

Con

v1·c

conv

_var

J:=3

*<1-

Lam

bda1

)*1n

tegV

a[+L

ambd

a1*C

1-SR

T1"

[N+1

J>;

end·

if

Kap

paP2

<>0

then

beg

in

for

Arb

lnde

x:=

O

to C

N+1

) do

ln

terG

2"[A

rbln

dexJ

:=C

1-S

RT

2"[A

rbln

dexJ

)*A

rbln

dex*

Oel

taE

*Arb

lnde

x*D

elta

E;

Inte

gra

teV

ecto

r(ln

terG

2",

Del

taE

,0,(

N+

1),

lnte

gV

al);

C

onv2

" [C

onv

Var

] :=

3*C

1-L

ambd

a2)*

1nte

gVal

+Lam

bda2

*C1-

SRT

2"[N

+1J)

; en

d;

-

end;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re G

raph

1 In

itia

lise

; '

begi

n -

init

SE

Gra

phic

s(1F

:\tp

61);

Set

Cur

rent

Win

dow

(2);

B

orde

rCur

rent

Win

dow

C1)

; S

etA

xesT

ype(

0,0)

; S

cale

Plo

tAre

a(0

.0,0

.0, 1

.0, 1

.0);

S

etX

Yln

terc

epts

(0.0

,0.0

);

Set

Col

or(2

);

Dra

wX

Axi

s(0.

2,1)

; D

raw

YA

xis(

0.2,

1);

Lab

elX

Axi

s(1,

0);

Lab

el Y

Axi

sC1

,0);

T

itle

XA

xisC

'Dim

ensi

onle

ss R

adiu

s');

T

itle

YA

xis(

'Dim

ensi

onle

ss C

on

cen

trat

ion

');

Tit

leW

indo

w('M

odel

2D2'

);

Str

(Bet

a1:6

:3,B

eta1

S);

S

tr(K

appa

P1:

6:3,

Kap

paP

1S);

S

tr((

Del

taT

*P

rin

t C

rit)

:6:4

,GD

TS

);

StrC

Lam

bda1

:5:3

,Lam

bda1

S);

Str

(Ord

SP

1:5:

2,0r

dSP

1S);

S

tr(B

eta2

:6:3

,Bet

a2S

);

Str

(Kap

paP

2:6:

3,K

appa

P2S

);

StrC

Lam

bda2

:5:3

,Lam

bda2

S);

Str

(Ord

SP

2:5:

2,0r

dSP

2S);

G

Labe

l 1:=

Con

cat(

1 B

eta1

',B

eta1

S, ';

K

appa

1 ',K

appa

P1S

, ';

La

mbd

a1

1 ,L

ambd

a1S

•·

Ord

er1

'Ord

SP

1S

•·

GOT

' G

DTS

)· G

Lab

el2:

=C

onca

tC'

Bet

a2

1,B

etaZ

S,1

; Kapp~2

',Kap

paP

2S,:

; La

mbd

a2

',Lam

bda2

S

. '·

Ord

er2

',Ord

SP

2S);

L

abel

Gra

phW

indo

wC

1,93

0,G

Lab

el1,

0,0)

; L

abel

Gra

phW

indo

w(1

,900

,Gla

bel2

,0,0

);

for

Arb

lnde

x:=O

to

N+1

do

Dat

aSet

X"[

Arb

lnde

xJ:=

Arb

lnde

x*D

elta

E;

Dat

aPoi

nts:

=N

+2;

en

d;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Page 161: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

0/19

95

15:0

1 F

ilen

ame:

M

ODEL

2D2.P

AS

Pag

7

Pro

cedu

re G

raph

1 R

esul

ts;

begi

n -

if K

appa

P1<>

0 th

en b

egin

fo

r A

rbln

dex:

=O

to (

N+1

) do

Dat

aSet

Y"[

Arb

lnde

xJ :=

AR

TP1.

[A

rbln

dexl

; L

ineP

lotD

ata(

Dat

aSet

x·,o

ataS

etY

",D

ataP

oint

s,3,

0);

for

Arb

lnde

x:=O

to

(N

+1)

do D

ataS

etY

"[A

rbln

dex]

:=S

RT

1P1"

[Arb

lnde

xJ;

Lin

ePlo

tDat

a(D

ataS

etX

",D

ataS

etY

",D

ataP

oint

s,5,

0);

end·

if

Kap

paP2

<>0

then

beg

in

for

Arb

lnde

x:=O

to

(N

+1)

do D

ataS

etY

" [A

rbln

dexl

:=A

RTP1

" [A

rbln

dexl

; L

ineP

lotD

ata(

Dat

aSet

x·,o

ataS

etY

" ,D

ataP

oin

ts,3

,0);

fo

r A

rbln

dex:

=O

to (

N+1

) do

Dat

aSet

Y"[

Arb

lnde

xJ:=

SRT

2P1"

[A

rbln

dexl

; ·

Lin

ePlo

tDat

a(D

ataS

etX

",D

ataS

etY

" ,D

ataP

oin

ts,4

,2);

en

d;

end;

(---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re G

raph

2_In

itia

lise

_and

_Dra

w;

begi

n Set

Cur

rent

Win

dow

(2);

B

orde

rCur

rent

Win

dow

(1);

S

etA

xesT

ype(

0,0)

; X

Axi

sMax

:=K

appa

P1*B

eta1

*Del

taT

*Rep

eats

; S

cale

Plo

tAre

aCO

.O,O

.O,G

f2M

axx,

1.0)

; S

etX

Yin

terc

epts

(0.0

,0.0

);-

Set

Col

or(2

);

Dra

wX

Axi

sCC

Gf2

Max

X/5

),1)

; D

raw

YA

xis(

0.2,

l);

Lab

elX

Axi

sC1,

0);

Lab

elY

Axi

sC1,

0>;

Tit

leX

Axi

sC'D

imen

sion

less

Rea

ctio

n Ti

me

(With

re

spec

t to

RXN

1

) [K

appa

P1*B

eta

1*T

aul'>

; T

itle

YA

xisC

'Fra

ctio

nal

Con

vers

ion'

);

Tit

leW

indo

w('M

odel

2D2'

);

Lab

elG

raph

Win

dow

(1,9

30,G

Lab

el1,

0,0)

; L

abel

Gra

phW

indo

wC

1,90

01G

lab

el2

,0,0

);

if K

appa

P1<>

0 th

en b

egin

fo

r A

rbln

dex:

=O

to C

onv

Var

do

be

gin

Dat

aSet

X"[

Arb

lnde

x]:=

Arb

lnde

x*P

rint

Cri

t*D

elta

T*K

appa

P1*

Bet

a1;

Dat

aSet

Y"[

Arb

lnde

xJ:=

Con

v1"[

Arb

lnde

xl;

end·

Dat~

SetY

. [0

]: =

O;

Dat

aPoi

nts:

=C

onv

Var

; L

ineP

lotD

ata(

Dat

iSet

X",

Dat

aSet

Y",

Dat

aPoi

nts,

5,0)

; en

if K

appa

P2<>

0 th

en b

egin

fo

r A

rbln

dex:

=O

to C

onv

Var

do

be

gin

Dat

aSet

X"[

Arb

lnde

x]::

Arb

lnde

x*P

rint

_Cri

t*D

elta

T*K

appa

P1*

Bet

a1;

Dat

aSet

Y"[

Arb

lnde

xJ:=

Con

v2"[

Arb

lnde

xl;

end·

Dat~

SetY

" [Q

] : =

O;

Dat

aPoi

nts:

=C

onv

Var

; L

ineP

lotD

ata(

Dat

iSet

x·,o

ataS

etY

" ,D

ataP

oin

ts,4

,2);

en

d;

end;

07/3

0/19

95

15:0

1 F

ilen

ame:

M

OD

EL2D

2.PA

S Pa

ge

8

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

{MAI

N PR

OGRA

M:

}

begi

n

new

(AR

T);

new

(SR

T1)

; ne

w(S

RT

2);

new

(YV

Ect

or>;

ne

w(

I nte

rG1)

; ne

w(C

onv1

);

new

(AM

atri

x);

new

(AR

TP1

); ne

w(S

RT

1P1)

; ne

w(S

RT

2P1)

; ne

w(D

ataS

etX

);

new

(lnt

erG

2);

new

(Con

v2);

ne

w(A

lnve

rse)

;

cl r

scr;

G

rap

hl_

Init

iali

se;

repe

ats:

=O

; N

orm

1:=1

; N

orm

2:=1

; P

lot

Var

:=O

; C

onv-

Var

:=O

;

new

(SR

T1P

1C);

new

(SR

T2P

1C);

new

(Dat

aSet

Y);

Tim

eU A

RT

and

SRTs

; G

uess

-SR

TsP

1;-

whi

le-

rep

eats

<I

tera

tio

ns

do

begi

n w

hile

(N

orm

l>N

orm

Cri

t) o

r (N

orm

2>N

orm

Cri

t) d

o be

gin

Cal

e A

Mat

rix

and

Y V

ecto

r;

-G

auss

Jord

anC

AM

atri

x",Y

Vec

tor·

,cN

+1)

,AR

TP

1-,A

inve

rse·

,AM

atD

et);

C

heck

C

onve

rgen

ce;

ReG

uess

SR

TsP1

; en

d;

-

Plo

t_V

ar:=

Plo

t_V

ar+

1;

if P

lot

Var

=P

rint

C

rit

then

beg

in

Gra

pn1_

Res

ults

; P

lot

Var

:=O

; C

onv-

var:

=C

onv

Var

+1;

Cal

e-C

onve

rsio

n;

end;

-

Upd

ate_

AR

T_a

nd_S

RT

s;

Gue

ss

SRTs

P1;

Nor

m1:

=1;

Nor

m2:

=1;

rep

eats

:=re

pea

ts+

1;

end;

read

ln(H

ardC

opy1

);

if

Har

dCop

y1=1

th

en b

egin

Sc

reen

Dum

pC3,

0,2,

1.5

,1.5

,0, 1

,0,e

rro

r);

end;

Cle

arW

indo

w;

Gra

ph2_

Init

iali

se_a

nd_D

raw

;

read

lnC

Har

dCop

y2);

Page 162: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

QJ

"' "-

Vl c.: "-N 0 N _, UJ 0 0 :i::

QJ E

"' c: QJ

.....

CJ

"'

"' °' °' 0 ,...., ,..._ CJ

~

'-0 '-'-QJ

CJ•

CJ•

"' c:~

"'"' QJ .o~

C:N QJ

.t:CJ ... ,....,· 7."0. NE >- :::i a.o 0 c: u QJ -0 QJ '- '-"'u ~(/') ....

-0 -0 .... c: c: ' QJ QJ .....

Page 163: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

Sta

rt.

Se

t/In

itia

lise

V

ari

ab

les.

De

term

ine

mo

de

l p

ara

me

ters

fn

(siz

e).

Ite

rate

in

Tim

e.

Ca

lcu

late

th

e n

ext

Alp

ha

and

S

igm

a V

ecto

rs w

ithin

th

e p

art

icle

.

See

ne

xt f

low

she

et f

or d

eta

ils.

Gra

ph

pro

file

s.

Gra

ph

co

nve

rsio

n v

ers

us

time.

En

d.

Unt

il co

nve

rge

nce

occ

urs

: ~

I G

uess

a b

ulk

flu

id r

ea

ge

nt

con

cen

tra

tio

n.

I I

I Ite

rate

in

siz

e cl

ass

es.

~

Gu

ess

a S

igm

a v

ect

or

for

the

pa

rtic

le.

Ca

lcu

late

th

e A

-Ma

trix

an

d Y

-Vec

tor.

Ca

lcu

late

th

e A

lph

a V

ecto

r.

Ca

lcu

late

th

e b

ulk

flu

id r

ea

ge

nt

con

cen

tra

tio

n. I

Ca

lcu

late

th

e S

igm

a V

ect

ors

usi

ng

th

e c

alc

ula

ted

Alp

ha

Vec

tor.

I

Ite

rate

un

til b

ulk

flu

id r

ea

ge

nt

an

d

all

sig

ma

ve

cto

rs c

on

verg

e.

oo

~

I>

0 0

-0

. c:

C'D

'C".

u;

0 '"1

=

C'D

~

] g -tll 9- C'D

(")

~

0

'""'

3 ~

~

g 0

~

c..

1(!)

'"1

-0

Ul

c:: •

'trj

e.

~

~ >

~

~

00

Q

= Q

-=

""1 ::r

...

...

C'D

Q,.

.....

(") =--~

~ ~ =

~

Q

3 Q

,.

~ ~

~ o.

KS

c,.

~-.

r;; ~

tll

,...

... n

8. 00

Q

• c,

. ("

) ~

::r

.§ &

I~

Vi

""1

Page 164: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

06/1

5/19

95

09:4

8 F

ilen

ame:

M

OD

EL5E

1.PA

S Pa

ge

Prog

ram

Mod

el5E

1;

{Mod

el5E

1.

{ *

Thi

s pr

ogra

m

is a

too

l fo

r *

The

prog

ram

cal

cula

tes

the

and

soli

d r

eact

ants

wit

hin

de

velo

ped

by D

ixon

.

anal

yzin

g TC

LP

dat

a.

} co

nce

ntr

atio

n p

rofi

le o

f fl

uid

}

{ { { { { { { { {

* T

his

prog

ram

onl

y pr

ovid

es a

part

icle

usi

ng

the

equa

tion

s as

) }

for

soli

d r

eact

ant

ord

ers

of

1.

}

*.A

ssum

ptio

ns

in

this

mod

el

incl

ude:

}

-Th

e so

lid

rea

ctan

t d

epo

sits

wit

hin

the

part

icle

}

rese

mbl

e th

ose

on

the

surf

ace.

}

The

dep

osi

ts

wou

ld b

oth

reac

t to

the

sam

e ex

ten

t }

if e

ach

wer

e ex

pose

d to

the

sam

e ac

id c

on

cen

trat

ion

}

for

the

sam

e ti

me.

}

{Cod

ed:

Gra

ham

Dav

ies.

}

{ D

epar

tmen

t of

Che

mic

al

Eng

inee

ring

. }

{ U

nive

rsit

y of

C

ape

Tow

n.

} {

28

Feb

ruar

y 19

95.

} {

29 M

ay

1995

Upd

ated

(G

MO

). }

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

{Dec

lara

tion

s:

}

uses

cr

t,st

dh

dr,

gj,

gra

ph

,wo

rld

dr,

seg

rap

h,i

nte

gra

t,M

2C

1B

ren

tRo

ots

;

cons

t

{***

The

se a

re t

he p

aram

eter

s ap

pli

cab

le t

o t

he

refe

ren

ce s

ize

clas

s.*

**

}

Bet

a1

Kap

paP1

Bet

a2

Kap

paP2

=10

.0;

=0.

12;

-O

:o:o

; V

oida

ge

=0.

01;

{Dim

ensi

onle

ss S

toic

hio

met

ric

rati

o d

efin

ed p

g 11

}

{Rat

io o

f re

atio

n r

ate

of s

oli

d r

eact

ant

resi

din

g

} {w

ithi

n th

e p

art

icle

to

por

ous

dif

fusi

on

of

flu

id

} {i

nto

the

part

icle

. D

efin

ed p

g 11

D

ixon

. }

{Voi

dage

of

the

soli

d p

arti

lces

.(P

oro

sity

) }

{***

The

se a

re p

aram

eter

s w

ith

rep

ect

to t

he C

STR

expe

rim

ent.

****

****

***}

Vol

liq

=0.

159;

{V

olum

e of

L

iqui

d L

ixiv

ian

t.

Cm3)

Tot

VoL

Part

=0.

577;

{T

otal

vo

lum

e o

f th

e so

lid

part

ilces.

M

=2;

{Num

ber

of s

ize c

lass

es.

Ref

Size

CL

=1

; {D

efin

es t

he

refe

ren

ce s

ize

clas

s.

}

} } }

{***

The

se a

re n

umer

ical

m

etho

d pa

ram

eter

s.**

****

****

****

****

****

****

***}

N

=19;

{H

alf

the

num

ber

of

inte

rio

r p

oin

ts.

r=O

an

d r=

R }

{not

in

clud

ed.

} D

el ta

E

=1/C

N+1

); {S

pace

In

crem

ent.

C

alcu

late

d f

rom

1/

(N+

1).

(Sin

ce}

{

R=i

*dE

and

R i

s at

po

int

N+

1.)

}

Del

taT

=

0.00

1;

Clim

e In

crem

ent.

}

Nor

m_C

rit

=1e

·6;

{Con

verg

ence

cri

teri

a b

ased

on

the

norm

of

vec

tor

}

06/1

5/19

95

09:4

8 F

ilen

ame:

M

OD

EL5E

1.PA

S Pa

ge

2

Con

v_C

rit

=1e

·8;

SCon

c To

l =

1e-4

· -

. M

axit

er

=100

;

Iter

atio

ns=

40

0;

Pri

nt

Cri

t=10

; V

iew

S1ze

CL

=2;

{***

}

{Con

verg

ence

cri

teri

a f

or

the

Bre

nt R

outi

ne.

} {D

imen

sion

less

co

nce

ntr

atio

n o

f so

lid

bel

ow

whi

ch

} {

it

is a

ssum

ed

to b

e n

egli

gib

le.

} {M

axim

um

itera

tio

ns

for

the

Bre

nt R

outi

ne.

}

{It

era

tio

ns

in t

ime.

}

{Det

erm

ined

fro

m d

esir

ed P

rin

t D

elta

T/D

elta

T

} {T

he c

on

cen

trat

ion

pro

file

s o

f-th

is s

izecla

ss a

re

} {g

raph

ed

in g

raph

1

. CN

B V

iew

Size

CL

<=

M

.) }

{***

Oth

er

info

rmat

ion

required.*****************************~**********}

Val

idD

ir

=1F

:\T

P6

1;{

Val

id d

irec

tory

fo

r g

rap

hic

s d

riv

ers.

Ord

SP1

Ord

SP2

=1.

0;

=1.

0;

{Rea

ctio

n o

rder

of

the

soli

d

in t

he

po

res.

{F

or

this

pro

gram

th

ese

need

to

be

set

at u

nit

y.

{See

Mod

el5D

2 fo

r v

aria

ble

ord

er r

eact

ion

ord

ers.

} } } }

type

var ar

ray1

= A

rray

[1 .

. 50,

1 ..

2]

of D

oubl

e;

Arb

ind

ex,S

izel

nd

ex,e

rro

r R

epea

ts,P

lot_

Var

,Con

v_V

ar,F

lag1

,Har

dCop

y C

onv1

,Con

v2,D

ataS

etX

,Dat

aSet

Y

: In

teg

er;

Bet

a1

k,B

eta2

k,K

appa

P1

k,K

appa

P2

k,K

appa

S1

k,K

appa

S2

k La

mbd

a1

k,L

amO

da2_

k,C

ontR

atio

V1,

Con

tRat

ioV

2--

: In

teg

er;

:"V

eryL

ongV

ecto

r;

:"S

ho

rtV

ecto

r;

Del

taT

K

A

RT

,AR

fP1,

SRT

1,SR

T2,

SRT

1P1,

SRT

2P1,

SRT

1P1C

,SR

T2P

1C

AM

atri

x,A

lnve

rse

AR

TP1

CV

al,S

um5i

zeD

ata_

2,N

uSta

r L

ambd

a1,L

ambd

a2,K

appa

S1,K

appa

S2

GL

abel

1,G

labe

l2

Siz

eDat

a :

Arr

ay[1

. .5

0, 1

. .2]

o

f R

eal;

CART

A

lpha

fn

(r)

at

tim

e T

{A

RTP1

A

lpha

fn

(r)

at

tim

e T+

1 {S

RT1

Sigm

a fn

(r)

at

tim

e T

{S

RTs

P1

Sigm

a fn

(r)

at

tim

e T+

1 (g

uess

ed)

: "S

hort

Vec

tor;

:"

Arr

ay1;

sqrM

at;

:·sq

rMat

; :E

xten

ded;

:E

xten

ded;

:S

trin

g;

rang

e O

.. M

0

.• N

+1}

rang

e O

•. M

0 ..

N+1

} ra

nge

O ••

M

0 •.

N+1

} ra

nge

O ••

M

0 ..

N+1

} {S

RTs

P1C

Si

gma

fn(r

) at

ti

me

T+1

(cal

cula

ted

) ra

nge

O .. M

0 ..

N+1

} C

YV

ect

'Co

nst

' v

ecto

r in

Cra

nk-N

icol

son

met

hod

rang

e O

•• N

+1

} {A

Mat

rix

Mat

rix

of C

rank

-Nic

olso

n co

effi

cien

ts

rang

e N*

N

}

{Oat

aSet

X

X v

ecto

r us

ed

in t

he

grap

hing

ro

uti

ne

rang

e O

•• N

+1

}

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re S

ize_

Dis

trib

uti

on

_In

itia

lisa

tio

n;

{Thi

s pr

oced

ure

sets

up

the

size

dis

trib

uti

on

dat

a ar

ray

. In

itia

lly

th

e }

{Siz

eDat

a ar

ray

co

nta

ins

rad

ius

info

rmat

ion

and

fr

acti

on

al

volu

me

} {i

nfor

mat

ion

Cie

R a

nd V

p/V

tot)

. O

n o

utp

ut

it c

on

tain

s re

lati

ve r

adiu

s }

{inf

orm

atio

n an

d re

lati

ve v

olum

e in

form

atio

n (

ie R

/R

ref

and

Vp/

Vp

ref)

. }

{Id

eall

y t

his

in

form

atio

n w

ould

be

re

ad

in f

rom

a

dat

a fi

le.

-}

var R

efR

adiu

s,V

oLR

efP

art

:Dou

ble;

(1

0 Q.. ~

t""' -· C

l) ~ -· = O' ..,. ~

0 Q..

. ~ Ul" ~ ~ . ~

00

.

Page 165: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

06/1

5/19

95

09:4

8 Fi

lena

me:

M

ODEL

5E1.P

AS

Page

3

begi

n Siz

eDat

a[1,

1J

=11

.35e

-3;

S ze

Dat

a [1

, 21

= 1

/100

Si

zeD

ata

[2, 1

l =

11.3

5e-3

; S

zeD

ata

[2, 2

1 =9

9/10

0 Si

zeD

ata

[3, 1

1 =

O.O

e-3;

S

zeD

ata

[3, 2

1 =

0/1

00

Si z

eDat

a [4

, 11

= O

.Oe-

3;

S ze

Dat

a[4,

2l

= 0

/100

S

izeD

ata[

5, 11

=

O.O

e-3;

S

zeD

ata

[5, 2

1 =

0/1

00

Siz

eDat

a[6,

1l

= O

.Oe-

3;

s ze

Dat

a[6,

2l

= 0

/100

Si

zeD

ata

[7, 1

l =

O.O

e-3;

s

zeD

ata[

7,2l

=

0/1

00

Siz

eDat

a[8,

1l

= O

.Oe-

3;

s ze

Dat

a [8

, 21

= 0

/100

S

zeD

ata

[9, 2

1 =

0/1

00

Siz

eDat

a[9,

1l

= O

.Oe-

3;

Siz

eDat

a[10

, 11

= O

.Oe-

3;

S ze

Dat

a[10

,2l

= 0

/100

Vol

Ref

Par

t:=

Tot

Vol

Par

t*S

izeD

ata[

Ref

Siz

eCl,

21;

Ref

Rad

ius

:=S

izeD

ata[

Ref

Siz

eCl,

11;

Sum

Size

Dat

a_2:

=0;

for

Siz

elnd

ex:=

1 to

M do

be

gin Siz

eDat

a[S

izel

ndex

, 11:

=S

izeD

ata[

Siz

elnd

ex,1

1/R

efR

adiu

s;

Siz

eDat

a[S

izel

ndex

,2l:

=S

izeD

ata[

Siz

elnd

ex,2

l*T

otV

olP

art/

Vol

Ref

Par

t;

Sum

Siz

eDat

a_2:

=S

umS

izeD

ata_

2+S

izeD

ata[

Siz

elnd

ex,2

l;

end;

·

NuS

tar:

=V

olL

•qtC

Voi

dage

*Vol

Ref

Part

);

{Rat

io o

f vo

lum

e of

bu

lk f

luid

to

flu

id

in p

arti

cle

pore

s.

}

end;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re C

onta

min

ant_

Loc

atio

n_ln

itia

lisa

tion

;

{Thi

s pr

oced

ure

is u

sed

to d

efin

e th

e co

ntam

inan

t ra

tio

vec

tor

(rati

o o

f }

{th

e su

rfac

e co

ntam

inan

t co

ncen

trat

ion

to b

ulk

cont

amin

ant

con

cen

trat

ion

).}

{NO

TE:

If a

ny s

ize

clas

s of

p

arti

cles

hav

e a

surf

ace

conc

entr

atio

n of

}

{ co

ntam

inan

t,

then

so

too

mus

t th

e re

fere

nce

size

cla

ss.

}

begi

n Con

tRat

oV

1"[1

l =O

: C

ontR

at

oV1

-C2l

=O;

Con

tRat

oV

1 -[

3l

=O;

Con

tRat

oV

1"[4

l =O

; C

ontR

at

oV1"

[5l

=O;

Con

tRat

oV

1 -[

6l

=O;

Con

tRat

oV

1 -[

7l

=O;

Con

tRat

oV

1 -[

8l

=O;

Con

tRat

oV

1 -[

9l

=O;

Con

tRat

oV

1"[1

0l

=O;

end;

Con

tRat

ov

2" [

1l

=O

Con

tRat

ov

2"[2

l =O

C

ontR

at

ov2"

[3l

=O

Con

tRat

ov

2"[4

l =O

C

ontR

at

ov2"

[5l·

=O

C

ontR

at

ov2"

[6l

=O

Con

tRat

ov

2"[7

l =O

C

ontR

at

ov2"

[8l

=O

Con

tRat

ov

2"[9

l =O

C

ontR

at

ov2"

[10l

=O

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re D

eter

min

e_M

odel

_Par

amet

ers_

fn_S

ize;

{Thi

s pr

oced

ure

dete

rmin

es

the

mod

el

para

met

ers

each

siz

e cl

as.s

of

{p

arti

cles

. } }

06/1

5/19

95

09:4

8 F

ilen

ame:

M

OD

EL5E

1.PA

S Pa

ge

4

var Fl

ag1,

Flag

.2

:In

teg

er;

begi

n F

lag1

:=0;

F

lag2

:=0;

fo

r S

izel

ndex

:=1

to M

do

begi

n Lam

bda1

k.

[S

izel

ndex

l :=

Con

tRat

ioV

1"[S

izel

ndex

l -

/(1+

Con

tRat

ioV

1"[S

izel

ndex

l >;

La

mbd

a2

k"[S

izel

ndex

l:=

Con

tRat

ioV

2"[S

izel

ndex

l -

/(1+

Con

tRat

ioV

2"[S

izel

ndex

l);

f C

ontR

atio

V1"

[Siz

elnd

exl<

>O

th

en F

lag1

:=F

lag1

+1;

f

Con

tRat

ioV

2"[S

izel

ndex

l<>

O

then

F

lag2

:=F

lag2

+1;

en

d

if

CC

CFl

ag1=

1>

and

(Con

tRat

ioV

1"[R

efS

izeC

ll=

0))

or

((F

lag2

=1)

an

d (C

ontR

atio

v2"[

Ref

Siz

eCll

=0)

))

then

beg

in

clo

sese

gra

ph

ics;

w

rite

lnC

'Con

tam

inan

t L

ocat

ion

Vio

loat

ion

.');

re

adln

; en

Lam

bda1

=L

ambd

a1

k"[R

efS

izeC

ll;

Lam

bda2

=

Lam

bda2

-k"[

Ref

Siz

eCll

; K

appa

S1

=Lam

bda1

*Kap

paP1

/(1-L

ambd

a1);

Kap

paS2

=L

ambd

a2*K

appa

P2/(

1-L

ambd

a2);

for

Siz

elnd

ex:=

1 to

M do

be

gin Del

taT

_k-[

Siz

elnd

ex,1

1 :=

Del

taT

/Siz

eDat

a[S

izel

ndex

,11

/Siz

eDat

a[S

izel

ndex

,11;

B

eta1

k"

[Siz

elnd

exl

:=B

eta1

*(1+

Con

tRat

ioV

1"[R

efS

izeC

ll)

-/(

1+C

ontR

atio

V1"

[Siz

elnd

exl)

; B

eta2

k"

[Siz

elnd

exl

:=B

eta2

*(1+

Con

tRat

ioV

2"[R

efS

izeC

ll)

-/(

1+C

ontR

atio

V2"

[Siz

elnd

exl)

; K

appa

P1

k"[S

izel

ndex

l :=

Kap

paP

1*S

izeD

ata[

Siz

elnd

ex,1

l -

*Siz

eDat

a[S

izel

ndex

, 11;

K

appa

P2

k" [

Siz

elnd

exl

:=K

appa

P2*

Siz

eDat

a[S

izel

ndex

, 11

-*S

izeD

ata[

Siz

elnd

ex,1

1;

{***

**N

ote:

Uni

ty p

ower

as

sum

ptio

n in

volv

ed i

n ne

xt

few

li

nes*

****

}

if C

ontR

atio

V1"

[Siz

elnd

exl=

O

then

Kap

paS1

k"

[Siz

elnd

exl

:=O

el

se

Kap

paS1

k"

[Siz

elnd

exl:

=K

appa

S1*

Con

tRat

ToV

1"[S

izel

ndex

l -

/Con

tRat

ioV

1"[R

efS

izeC

ll*S

izeD

ata[

Siz

elnd

ex, 1

1;

if C

ontR

atio

V2"

[Siz

elnd

exl=

O

then

Kap

paS2

k"

[Siz

elnd

exl

:=O

el

se

Kap

paS2

k"

[Siz

elnd

exl:

=K

appa

S2*

Con

tRat

ToV

2"[S

izel

ndex

l -

/Con

tRat

ioV

2"[R

efS

izeC

ll*S

izeD

ata[

Siz

elnd

ex, 1

1;

end·

en

' {--~----------------------

------------------------------------------------}

Pro

cedu

re T

imeO

_AR

T_an

d_SR

Ts;

{Thi

s pr

oced

ure

uses

th

e in

itia

l co

ndit

ions

to

set

the

alp

ha a

nd s

igm

a }

{vec

tors

. }

{Not

e th

at A

RT[

N+1

l, A

RTP

1[N

+1l,

SRT1

[N

+1l

and

SRT1

P1[N

+1l

are

the

surf

ace}

{c

once

ntra

tion

s of

th

e li

qu

id a

nd s

oli

d r

eact

ants

. }

begi

n for

Siz

elnd

ex:=

1 to

M do

Page 166: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

06/1

5/19

95

09:4

8 Fi

lena

me:

M

ODEL

5E1.P

AS

Page

5

begi

n for

Arb

lnde

x:=O

to

N d

o be

gin AR

T"[

Size

lnde

x,A

rbln

dex]

=O

S

RT

1"[S

izel

ndex

,Arb

lnde

xl

=1

SR

T2"

[Siz

elnd

ex,A

rbln

dex]

=1

en

AR

Tt[

Size

lnde

x,N

+1l

=1

SRT

1"[S

izei

ndex

,N+1

l =1

SR

T2"

CSi

zeln

dex,

N+1

J =1

en

for'

arb

lnde

x:=

O

to m

axv

do

begi

n C

onv1

"[A

rbln

dexJ

:=O

; C

onv2

"[A

rbln

dexl

:=O

; en

end;

'

{---

----

----

----

----

----

----

·---

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re G

uess

_SR

TsP1

;

{Thi

s pr

oced

ure

prov

ides

the

in

itia

l "g

uess

" fo

r th

e it

erat

ion

. It

use

s }

{the

pre

viou

s ti

me

inte

rval

's v

alue

s as

the

gue

ss.

}

begi

n for

Siz

eind

ex:=

1 to

M do

be

gin

' fo

r A

rbin

dex:

=O

to C

N+1

) do

be

gin SR

T1P

1"[S

izei

ndex

,Arb

lnde

xl:=

SR

T1"

CS

izel

ndex

,Arb

lnde

xl;

SR

T2P

1"[S

izel

ndex

,Arb

lnde

xJ:=

SR

T2"

[Siz

eind

ex,A

rbln

dexJ

; en

ARTP

1 · C

Size

inde

x,N

+1]

:=A

RT"

CSi

zeir

dex,

N+1

J ;.

end·

en

d;

'

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re R

eGue

ss_S

RTs

P1;

{Thi

s pr

oced

ure

prov

ides

an

upda

ted

"gue

ss"

for

the

next

it

erat

ion

. It

{u

ses

the

SRT1

P1C

vect

or a

s th

e up

date

d gu

ess.

begi

n for

Siz

eind

ex:=

1 to

M do

be

gin fo

r A

rbln

dex:

=O

to C

N+1

) do

be

gin SR

T1P

1"[S

izei

ndex

,Arb

lnde

xJ :

=SR

T1P

1C"[

Size

lnde

x,A

rbln

dexJ

; SR

T2P

1"[S

izel

ndex

,Arb

lnde

x] :

=SR

T2P

1C"[

Size

inde

x,A

rbln

dexJ

; en

AR

TP1

"[Si

zeln

dex,

N+1

J:=A

RT

P1C

Val

; en

d;

end;

} }

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re C

alc_

Cra

nk_N

icol

son_

Mat

rix(

var

YV

ecto

r :S

hort

Vec

tor)

;

{***

**N

ote:

Uni

,ty p

ower

as

sum

ptio

n in

volv

ed i

n th

is p

roce

dure

****

*

var R

ows,

Col

s : I

nteg

er;

}

06/1

5/19

95

09:4

8 F

ilen

ame:

M

OD

EL5E

1.PA

S Pa

ge

6

begi

n for

Row

s:=O

to

(N

+1)

do

begi

n for

Col

s:=O

to

{N

+1)

do A

Mat

rix"

[Row

s,C

ols]

:=O

; en

d;

AM

atri

x"[O

,OJ:

=C

-6-D

elta

E*D

elta

E*S

izeD

ata[

Siz

elnd

ex,1

J*S

izeD

ata[

Siz

elnd

ex,1

J *(

Kap

paP1

k"

[Siz

elnd

exJ*

SR

T1P

1"C

Siz

eind

ex,O

J +K

appa

P2 k

"[S

izei

ndex

J*S

RT

2P1"

[Siz

eind

ex,0

J)-2

*Del

taE

*Del

taE

*S

izeD

ataC

Siz

eind

ex, 1

J*S

izeD

ata[

Siz

elnd

ex,1

J /O

elta

T

k"[

Siz

ein

dex

,1J)

; A

Mat

rix·

CO,

1]

:=6;

-

YV

ecto

r[O

J :=

AR

T"[

Siz

elnd

ex,0

]*(6

+D

elta

E*D

elta

E*S

izeO

ata[

Siz

elnd

ex, 1

] *S

izeD

ata[

Siz

elnd

ex, 1

l*C

Kap

paP

1_k.

[Siz

eind

ex]

*SR

T1"

[Siz

elnd

ex,O

J+K

appa

P2

k"[S

izei

ndex

J *S

RT

2"[S

izel

ndex

,0])

-2*D

elta

E*O

elta

E*S

izeD

ata[

Siz

eind

ex, 1

1 *S

izeD

ata[

Siz

elnd

ex,1

1/D

elta

T k

"[S

izei

ndex

, 1])

-A

RT

"[S

izei

ndex

,1]*

6;

-

for

Row

s:=1

to N

-1

do

begi

n AM

atri

x"[R

ows,

Row

s·1J

:=R

ows·

1;

AM

atri

x"[R

ows,

Row

s]

:=-2

*Row

s-R

ows*

Del

taE

*Del

taE

*Siz

eDat

a[S

izel

ndex

,1]

*Siz

eDat

a[S

izei

ndex

,1l*

CK

appa

P1_

k·cs

izei

ndex

]*

SRT

1P1"

CSi

zeln

dex,

Row

s]+K

appa

P2

k"[S

izei

ndex

]*

SR

T2P

1"[S

izel

ndex

,Row

s])-

2*R

ows•

oelt

aE

*Del

taE

*Siz

eDat

a[S

izei

ndex

,1]

*Siz

eDat

aCS

izei

ndex

,1l/

Del

taT

_k·c

size

inde

x, 1

1;

AM

atri

x"[R

ows,

Row

s+1]

:=R

ows+

1;

YV

ecto

r[R

owsl

:=

AR

T"[

Size

inde

x,R

ows-

1J*(

-Row

s+1)

+

AR

T"[

Size

inde

x,R

owsl

*C2*

Row

s+R

ows*

Del

taE

*Oel

taE

*S

izeD

ata[

Siz

eind

ex,1

J*S

izeD

ata[

Siz

eind

ex,1

l *C

Kap

paP1

k"

[Siz

eind

exJ*

SR

T1"

CS

izei

ndex

,Row

sJ

+Kap

paP2

k"[

Siz

elri

dexJ

*SR

T2"

[Siz

elnd

ex,R

owsl

) -2

*Row

s*D

elta

E*D

elta

E*S

izeD

ata[

Siz

eind

ex,1

l *S

izeD

ataC

Siz

elnd

ex,1

1/D

elta

T_k

·csi

zeln

dex,

1])

+AR

T"[

Size

lnde

x,R

ows+

1l*C

-Row

s-1)

; en

d;

AM

atri

x · C

N, N

-1 l :

=N-1

; A

Mat

rix"

[N,N

l :=

-2*N

-N*D

elta

E*D

elta

E*S

izeD

ata[

Siz

eind

ex,1

l *S

izeD

ata[

Siz

elnd

ex,1

l*C

Kap

paP

1 k"

CS

izei

ndex

l *S

RT

1P1"

[Siz

eind

ex,N

J+K

appa

P2 k

~[Sizeindexl

*SR

T2P

1"[S

izel

ndex

,Nl)

-2*N

*DeT

taE

*Del

taE

*S

izeD

ataC

Siz

eind

ex, 1

l*S

izeD

ata[

Siz

eind

ex, 1

J .

/Del

taT

k

"[S

izel

nd

ex,1

l;

YV

ecto

rCN

l :=

AR

T"[

Size

lnde

x,N

-1l*

C-N

+1)+

AR

T"[

Size

inde

x,N

l*C

2*N

+ N

*Del

taE

*Del

taE

*Siz

eDat

a[S

izei

ndex

,1]

*Siz

eDat

a[S

izei

ndex

,1l*

CK

appa

P1

k"[S

izel

ndex

l *S

RT

1"[S

izei

ndex

,NJ+

Kap

paP2

k"[

Siz

eind

ex]

*SR

T2"

[Siz

elnd

ex,N

J)-2

*N*D

eTta

E*D

elta

E

*Siz

eDat

a[S

izei

ndex

,1J*

Siz

eDat

a[S

izei

ndex

,1J

/Del

taT

k"

CS

izei

ndex

,1l)

+A

RT

"[S

izei

ndex

,N+

1l*C

-N-1

) -A

RT

P1"1

Size

lnde

x,N

+1J*

{N+1

);

end;

{·--

----

----

----

----

----

----

----

----

----

----

----

-···

··-·

----

----

----

----

--}

Pro

cedu

re C

alc_

AR

TP1_

and_

SRTs

P1C

;

Page 167: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

06/1

5/19

95

09:4

8 Fi

lena

me:

M

ODEL

5E1.P

AS

Page

7

{As

it s

tand

s th

is p

roce

dure

can

cop

e w

ith

a v

aria

ble

rea

ctio

n o

rder

. T

his}

{

is d

ue

to t

he

incl

usio

n of

th

e B

rent

Rou

tine

. }

var M

assB

alV

al,A

Mat

Det

V

alue

AtR

oot

Out

putV

ecto

r,Y

Vec

tor

Dou

ble;

R

eal;

S

hort

Vec

tor;

begi

n {F

irst

cal

cula

te t

he A

RTP1

v

ecto

rs.

for

Siz

elnd

ex:=

1 to

M do

be

gin Cal

e C

rank

N

icol

son

Mat

rixC

YV

ecto

r);

GaussJordanCAMatrix~,YVector,CN+1),0utputVector,Alnverse·,AMatDet);

}

for

Arb

lnde

x:=O

to

N d

o A

RT

P1"[

Size

lnde

x,A

rbln

dex]

:=

Out

putV

ecto

r[A

rbln

dexJ

;

end;

{The

Gau

ssJo

rdan

pro

cedu

re c

alcu

late

s va

lues

for

th

e AR

T ve

ctor

fr

om

{poi

nt 0

to

poin

t N

(al

thou

gh it

mak

es

use

of.

the

N+1

th p

oin

t).

To

{det

erm

ine

the

N+1

th p

oint

val

ue,

mak

e us

e of

th

e m

ass

bala

nce

of

{fl

uid

rea

ctan

t in

-th

e CS

TR.

Mas

sBal

Val

:=O

;

for

Siz

elnd

ex:=

1 to

M do

be

gin

} } } )

Mas

sBal

Val

:=M

assB

alV

al-S

izeD

ata[

Size

lnde

x,2J

/2*C

Kap

paS1

k"

[Siz

elnd

ex]

*SR

T1"

[Siz

elnd

ex,(

N+

1)J*

AR

T'[S

izel

ndex

,(N

+1)

J

end;

+Kap

paS1

k"

[Siz

elnd

exJ*

SR

T1P

1"[S

izel

ndex

,CN

+1)

l *A

RT

P1"[

Size

lnde

x,(N

+1)J

+Kap

paS2

k"[

Siz

elnd

exJ

*SR

T2"

[Siz

elnd

ex,(

N+

1)J*

AR

T"[

Siz

elnd

ex,(

N+

1)l

+K

appa

S2_k

"[Si

zeln

dexJ

*SR

T2P

1"[S

izel

ndex

,(N

+1)

l *A

RT

P1"

[Siz

elnd

ex,(

N+

1)J)

-3*S

izeD

ata[

Siz

elnd

ex,2

l /C

Siz

eDat

a[S

i.:e

lnde

x, 1

J*S

izeD

ata[

Siz

elnd

ex,1

J)/2

*C

CA

RT

"[Si

zeln

dex,

(N+1

)J+A

RT

P1"[

Size

lnde

x,C

N+1

)J)

·CA

RT

"[S

izel

ndex

,NJ+

AR

TP

1"[S

izel

ndex

,NJ)

)/D

elta

E;

AR

TP1

CV

al:=

AR

T"[

1,(N

+1)J

+Del

taT

/NuS

tar*

Mas

sBal

Val

;

{Cal

cula

te t

he S

RTsP

1C

vec

tors

. C

ode

mak

es

use

of

Bre

nt'

s M

etho

d }

CCA

non-

line

ar

root

fi

ndin

g pr

oced

ure)

to

sol

ve f

or

the

roo

t.

)

for

Siz

elnd

ex:=

1 to

M do

be

gin fo

r A

rbln

dex:

=O

to.

CN+1

) do

be

gin

if (

Bet

a1_k

"[S

izel

ndex

l<>

O)

and

(Kap

paP1

_k"[

Size

lnde

xJ<

>0)

th

en

begi

n if O

rdSP

1=1

then

be

gin SR

T1P

1C"[

Siz

elnd

ex,A

rbln

dexJ

:=S

RT

1"[S

izel

ndex

,Arb

lnde

xJ

*(1-

Del

taT

k"[

Siz

elnd

ex,1

J*K

appa

P1

k"[S

izel

ndex

l *B

eta1

k"

[Siz

elnd

exJ*

AR

T"[

Siz

elnd

ex,A

rbln

dexl

/C

2*C

FLam

bda1

k"

[S

izel

ndex

l ))

)/(1

+D

el ta

T

k" [

Siz

elnd

ex, 1

] *K

appa

P1_

k"[S

izel

ndex

l*B

eta1

_k· [

Siz

elnd

exT

.

06/1

5/19

95

09:4

8 F

ilen

ame:

M

OD

EL5E

1.PA

S Pa

ge

8

ex, 1

J,

*AR

TP

1"[S

izel

ndex

,Arb

lnde

xl/C

2*C

1-L

ambd

a1_k

.[S

izel

ndex

J)))

end

else

if

SR

T1P

1"[S

izel

ndex

,Arb

lnde

xJ<

SCon

c To

l th

en

SR

T1P

1C"(

Siz

elnd

ex,A

rbln

dexJ

:=S

RT

1P1"

CS

izel

ndex

,Arb

lnde

xJ

else

be

gin SR

T1P

1C"C

Siz

elnd

ex,A

rbln

dexJ

:=B

rent

Roo

ts(0

.0,1

.0,D

elta

T_k

-CS

izel

nd

Kap

paP1

k"

CS

izel

ndex

J,B

eta1

k"

[Siz

elnd

ex],

L

ambd

a1-k

"(S

izel

ndex

J,O

rdS

PT

,AR

T"[

Siz

elnd

ex,A

rbln

dex]

, A

RT

P1"C

Size

lnde

x,A

rbln

dexl

,SR

T1"

[S

izel

ndex

,Arb

lnde

x],

1e·8

, 100

,Val

ueA

tRoo

t,er

ror)

; en

end·

'

if

CB

eta2

k"

[Siz

elnd

exJ<

>O

) an

d (K

appa

P2

k"[S

izel

ndex

]<>

O)

then

be

gin

--

if O

rdSP

2=1

then

be

gin SR

T2P

1C"[

Siz

elnd

ex,A

rbln

dexJ

:=S

RT

2"[S

izel

ndex

,Arb

lnde

xl

end

*(1-

Del

taT

k"

CS

izel

ndex

, 1l*

Kap

paP2

k"

[S

izel

ndex

] *B

eta2

k"

Csi

zeln

dexl

*AR

T"[

Siz

elnd

ex,A

rbln

dexl

/(2*C1~Lambda2

k"[S

izel

ndex

])))

/(1+

Del

taT

k"

[Siz

elnd

ex, 1

1 *K

appa

P2

k"C

Siz

elnd

exl*

Bet

a2_k

·csi

zeln

dex]

*A

RT

P1"

Csi

zeln

dex,

Arb

lnde

xl/C

2*C

1-L

ambd

a2_k

·csi

zeln

dex]

)))

else

if

SRT

2P1"

CSi

zeln

dex,

Arb

lnde

xJ<S

Con

c To

l th

en

SR

T1P

1C"[

Siz

elnd

ex,A

rbln

dexl

:=S

RT

2P1"

[Siz

elnd

ex,A

rbln

dexJ

el

se

begi

n SR

T2P

1C"[

Siz

elnd

ex,A

rbln

dexJ

:=B

rent

Roo

ts(0

.0, 1

.0,

Del

taT

k"

CS

izel

ndex

,1l,

Kap

paP

2 k"

[Siz

elnd

ex],

B

eta2

K0

[Siz

elnd

ex],

Lam

bda2

_k"l

Siz

elnd

ex],

Ord

SP

2,

AR

T"[

Siz

elnd

ex,A

rbln

dexJ

,AR

TP

1"[S

izel

ndex

,Arb

lnde

x],

SR

T2"

CS

izel

ndex

,Arb

lnde

xJ,1

e·8,

100,

Val

ueA

tRoo

t,er

ror)

; en

end·

'

end·

'

end·

'

end;

'

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re C

heck

_Con

verg

ence

;

{Thi

s pr

oced

ure

chec

ks w

heth

er o

r no

t th

e so

luti

on

has

co

nver

ged

by

} {c

ompa

ring

th

e gu

esse

d va

lue

of S

RT1P

1 w

ith

a ca

lcu

late

d v

alue

of

SRT1

P1.

} {A

lso

com

pare

s th

e ca

lcu

late

d v

alue

of

ARTP

1C

wit

h gu

esse

d va

lue

of

} {A

RTP

1.

)

var N

orm

1,N

orm

2,N

orm

3

begi

n Nor

m1

=O;

{Usi

ng a

nor

m *

**

Nor

m2

=O;

Nor

m3

=O;

for

S ze

lnde

x:=

1 to

M do

be

gin

:Dou

ble;

}

Page 168: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

_,.

06/1

5/19

95

09:4

8 Fi

lena

me:

M

OO

EL5E

1.PA

S Pa

ge

9

for

Arb

lnde

x:=O

to

(N

+1)

do

begi

if (

Bet

a1_k

.[S

izel

ndex

l<>

0) a

nd

(Kap

paP

l_k.

[Siz

elnd

exJ<

>O

) th

en b

egin

N

orm

l:=N

orm

l+(S

RT

1Plc

· [S

izel

ndex

,Arb

lnde

xl

·SR

T1P

l"[S

izel

ndex

,Arb

lnde

xJ)*

(SR

T1P

1C. [

Siz

elnd

ex,A

rbin

dexJ

-S

RT1

P1. [

Siz

elnd

ex,A

rbln

dexl

);

end

else

Nor

ml:=

O;

if (

Bet

a2

k"[S

izel

ndex

]<>

O)

and

(Kap

paP2

k"

[Siz

eind

ex]<

>O

) th

en b

egin

N

orm

2:=N

orm

2+(S

RT

2Plc

·csi

zeln

dex,

Arb

lnde

xJ

-SR

T2P1

" [S

izel

ndex

,Arb

lnde

xl )

*(SR

T1P

lc·

[Siz

elnd

ex,A

rbln

dexl

-S

RT2

P1. [

Siz

elnd

ex,A

rbln

dexl

>;

end

else

Nor

m2:

=0;

end·

en

' Nor~

:=(A

RTP1

CVal

-ART

P1.

[1,N

+ll

)*(A

RT

PlC

Val

-AR

TPl

. [1,

N+

ll )

; if

(N

orm

l<N

orm

Cri

t) a

nd

(Nor

m2<

Nor

m C

rit)

and

(N

orm

3<N

orm

Cri

t)

then

Fla

gl:

=l;

-

-en

d;

{---

----

----

----

----

-:·-

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re U

pdat

e_A

RT_

and_

SRTs

;

{Thi

s pr

oced

ure

upda

tes

the

alph

a an

d si

gma

vect

ors

for

the

next

it

erat

ion

}

{by

repl

acin

g th

eir

com

pone

nts

with

th

e al

phaT

+l

and

sigm

aT+l

v

ecto

rs.

}

begi

n for

Siz

elnd

ex:=

l to

M do

be

gin fo

r A

rbln

dex:

=O

to (

N+l

) do

be

gin ART"[Sizelndex,Arblnd~x]

=A

RT

Pl"

[Siz

elnd

ex,A

rbin

dexl

; S

RT

l"[S

izel

ndex

,Arb

lnde

xl

=S

RT

1P1"

[Siz

elnd

ex,A

rbln

dexJ

; S

RT

2"[S

izel

ndex

,Arb

lnde

xl

=S

RT

2P1"

[Siz

elnd

ex,A

rbln

dexJ

; en

end·

'

end;

'

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re C

alc_

Con

vers

ion;

{Thi

s pr

oced

ure ~a

lculat

es

the

frac

tio

nal

co

nver

sion

of

the

par

ticl

e fo

r }

{th

e ti

me

inte

rval

. It

use

s th

e fo

rmul

a on

pg.

13

Oix

on.

The

inte

gra

tor}

{

is t

he Q

uinn

-Cur

tis

vect

or

inte

gra

tor.

}

var In

terG

1 ln

terG

2 ln

tegv

al,c

onve

rsio

n :V

eryL

ongV

ecto

r;

:Rea

l;

begi

n for

Siz

elnd

ex:=

1 to

M do

be

gin if K

appa

P1

k"[S

izel

ndex

J<>

O

then

be

gin

for

Arb

!nde

x:=O

to

(N

+1)

do

lnte

rG1[

Arb

lnde

xJ:=

(1-S

RT

1"[S

izel

ndex

,Arb

lnde

xJ)*

Arb

lnde

x*O

elta

E

*Arb

lnde

x*D

elta

E;

lnte

grat

eVec

tor(

lnte

rG1,

Del

taE

,0,(

N+

1),l

nteg

Val

);

06/1

5/19

95

09:4

8 fi

lena

me:

M

OO

EL5E

1.PA

S Pa

ge

10

Con

vers

ion

:=3*

(1-L

ambd

a1

k"[S

izel

ndex

l)*l

nteg

Val

+L

ambd

a1

k"[S

izel

ndex

J*(1

-SR

T1"

[Siz

elnd

ex,N

+1l

>;

Con

v1"[

Con

v V

ar]

:=C

onv1

·cco

nv V

ar]+

Con

vers

ion*

Siz

e0at

a[S

izel

ndex

,2J

-/S

umSi

zeO

ata_

2;

end;

if K

appa

P2_k

·csi

zeln

dexJ

<>

O

then

be

gin fo

r A

rbln

dex:

=O

to

(N+1

) do

Jn

terG

2[A

rbln

dexJ

:=(1

-SR

T2"

[Siz

elnd

ex,A

rbln

dexJ

)*A

rbln

dex*

Oel

taE

*A

rbln

dex*

Oel

taE

; ln

teg

rate

Vec

tor(

lnte

rG2

,Del

taE

,0,(

N+

1),

lnte

gV

al);

C

onve

rsio

n :=3*C1-Lambda2_k.[SizelndexJ)~lntegVal

+L

ambd

a2_k

.[S

izel

ndex

J*(1

-SR

T2"

[Siz

elnd

ex,N

+ll

);

Con

v2·c

conv

Var

) :=

Con

v2"[

Con

v V

arJ+

Con

vers

ion*

Siz

eOat

a[S

izel

ndex

,2J

-/S

umSi

zeO

ata_

2;

end·

en

' en

d;

'

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re G

raph

1_1n

itia

lise

;

var B

eta1

S,K

appa

P1S,

Lam

bda1

S,G

OT

S B

eta2

S,K

appa

P2S,

Lam

bda2

S .

Vie

wSi

zeC

lS

stri

ng

st

rin

g

stri

ng

begi

n init

SE

Gra

phic

s(V

alid

Oir

);

Set

Cur

rent

Win

dow

(2);

B

orde

rCur

rent

Win

dow

(1);

S

etA

xesT

ype(

0,0)

; S

cale

Plo

tAre

a(0

.0,0

.0,1

.0,1

.0);

S

etX

Yln

terc

epts

(0.0

,0.0

);

SetC

olor

C2>

; D

raw

XA

xisC

0.2,

1>;

Dra

wY

Axi

s(0.

2,1)

; L

abel

XA

xisC

1,0)

; L

abel

YA

xis(

1,0)

; T

itle

XA

xis(

'Dim

ensi

onle

ss R

adiu

s');

T

itle

YA

xis(

'Dim

ensi

onle

ss C

on

cen

trat

ion

');

Tit

leW

indo

wC

'Mod

el5E

1');

S

tr(B

eta1

k"

[Vie

wS

izeC

l]:6

:3,B

eta1

S);

Str(Kappa~1

k"[V

iew

Size

Cll

:6:

3,K

appa

P1S

);

Str

((D

elta

r•P

rin

t C

rit)

:6:4

,GD

TS

);

Str(

Lam

bda1

k"

[Vie

wSi

zeC

lJ :

5:3,

Lam

bda1

S);

S

tr(B

eta2

k~[ViewSizeClJ:6:3,Beta2S>;

Str(Kappa~2

k"[V

iew

Siz

eCll

:6:

3,K

appa

P2S

);

Str

(Lam

bda2

=k·

cvie

wS

izeC

ll :

5:3,

Lam

bda2

S);

S

trC

Vie

wS

izeC

l:2,

Vie

wS

izeC

lS);

G

labe

l1:=

Con

cat(

' B

eta1

',

Bet

a1S

,';

Kap

pa1

',Kap

paP

1S,';

La

mbd

a1

Lam

bda1

S,';

GOT

wrt

R

efS

izeC

lass

',G

DT

S);

GL

abel

2:=

Con

cat(

' B

eta2

',

Bet

a2S

,';

Kap

pa2

',Kap

paP

2S,';

La

mbd

a2

Lam

bda2

S,';

Vie

wC

lass

',V

iew

Siz

eClS

);

Lab

elG

raph

Win

dow

(1,9

30,G

Lab

el1,

0,0)

; L

abel

Gra

phW

indo

w(1

,900

,Gla

bel2

,0,0

);

end;

Page 169: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

06/1

5/19

95

09:4

8 Fi

lena

me:

M

ODEL

5E1.P

AS

Page

11

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re G

raph

1_R

esul

ts;

begi

n if V

iew

Size

Cl>

M

then

be

gin Clo

sese

grap

hics

; w

rite

lnC

'Gra

ph

1 D

raw

ER

RO

R');

w

rite

ln('

You

hav

e in

stu

cted

the

Gra

phin

g R

outi

ne

to g

raph

th

e co

nv

ersi

on

');

wri

teln

('cu

rves

of

a si

ze c

lass

whi

ch

does

no

t ex

ist.

');

wri

teln

('R

esp

ecif

y =

Vie

wSi

zeC

lass

in

Dec

lara

tion

s se

ctio

n'>

; re

adln

; en

Siz~lndex:=ViewSiz

eCl;

for

Arb

lnde

x:=O

to

(N

+1)

do D

ataS

etx·

[A

rbln

dexl

:=

Arb

lnde

x*D

elta

E;

if K

appa

P1

k"[S

izel

ndex

]<>

O

then

beg

in

for

Arb

Tnde

x:=O

to

(N

+1)

do

Dat

aSet

Y"[

Arb

lnde

xJ:=

AR

TP

1"[S

izel

ndex

,Arb

lnde

xJ;

Lin

ePlo

tDat

a(D

ataS

etX

" ,D

ataS

etY

" ,(N+2~,3,0);

for

Arb

lnde

x:=O

to

CN

+1)

do

Dat

aSet

Y"C

Arb

lnde

xJ:=

SRT

1P1"

CSi

zeln

dex,

Arb

lnde

x];

Lin

ePlo

tDat

a(D

ataS

etX

",D

ataS

etY

" ,(

N+

2),5

, 1);

en

if K

appa

P2

k"[S

izel

ndex

]<>

O

then

beg

in

for

Arb

Tnde

x:=O

to

(N

+1)

do

Dat

aSet

Y"[

Arb

lnde

xl :=

ART

P1"

[Siz

elnd

ex,A

rbln

dexJ

; L

ineP

lotD

ata(

Dat

aSet

x-,D

ataS

etY

" ,(

N+

2),3

, 1);

fo

r A

rbln

dex:

=O .

to (

N+1

) do

D

ataS

etY

"[A

rbln

dex]

:=

SR

T2P

1"[S

izel

ndex

,Arb

lnde

xJ;

Lin

ePlo

tDat

a(D

ataS

etX

",D

ataS

etv·

,(N

+2)

,4,2

);

end;

end;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re G

raph

2_1n

itia

lise

_and

_Dra

w;

var XA

x i sM

ax

:Rea

l;

begi

n SetC

urre

ntW

indo

w(2

);

Bor

derC

urre

ntW

indo

w(1

);

SetA

xesT

ypeC

0,0)

; X

Axi

sMax

:=5;

C

****

*Del

taT

*Rep

eats

;***

*)

Sca

leP

lotA

rea(

0.0,

0.0,

XA

xisM

ax, 1

.0);

S

etX

Yln

terc

epts

(O.O

,O.O

>;

Set

Col

orC

2l;

Dra

wX

Axi

sCC

XA

xisM

ax/5

), 1

);

Dra

wY

Axi

s(0.

2, 1

);

Lab

elX

Axi

s(1,

0);

Lab

elY

Axi

sC1,

0);

Tit

leX

Axi

sC'D

imen

sion

less

Rea

ctio

n Ti

me

(WRT

R

efer

ence

Part

icle

)');

T

itle

YA

xis(

'Fra

ctio

nal

Con

vers

ion'

);

Titl

ewin

dow

('Mod

el5E

1 ')

;

06/1

5/19

95

09:4

8 F

ilen

ame:

M

OD

EL5E

1.PA

S Pa

ge

12

Lab

elG

raph

Win

dow

(1,9

30,G

Lab

el1,

0,0)

; L

abel

Gra

phW

indo

wC

1,90

0,G

labe

l2,0

,0);

if

Kap

paP1

k"

[Siz

elnd

ex]<

>O

th

en b

egin

fo

r A

rbT

ndex

:=O

to

Con

v V

ar

do

begi

n D

ataS

etX

"[A

rbln

dexJ

:;A

rbln

dex*

Pri

nt C

rit*

Del

taT

; D

ataS

etY

"CA

rbln

dexJ

:=C

onv1

"CA

rbln

dexJ

; en

Dat~SetY"[OJ :=

O;

Lin

ePlo

tDat

a(D

ataS

etX

" ,D

ataS

etY

",C

onv

Var

,5,0

>;

end·

-

if K

appa

P2

k"[S

izel

ndex

]<>

O

then

beg

in

for

Arb

Tnd

ex:=

O

to C

onv

Var

do

be

gin

Dat

aSet

X"[

Arb

lnde

x] :

;Arb

lnde

x*P

rint

_Cri

t*D

elta

T;

Dat

aSet

Y"C

Arb

lnde

x] :

=C

onv2

"[A

rbln

dexl

; en

Dat~

SetY

"[OJ

:=O;

L

ineP

lotD

ata(

Dat

aSet

X",

Dat

aSet

v· ,C

onv

Var

,4,0

);

end;

-

end;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

begi

n new

(Bet

a1

k);

new

(Kap

paP1

_k>;

ne

w(K

appa

S1_k

);

new

(Lam

bda1

k)

; ne

w(C

ontR

atT

oV1)

; ne

w(A

RT)

; ne

w(S

RT

1);

new

(SR

T2)

; ne

w(C

onv1

);

new

(Dat

aSet

X);

ne

w(A

Mat

rix)

;

cl r

scr;

new

(Bet

a2

k);

new

(Kap

paP2

_k);

ne

w(K

appa

S2_k

);

new

(Lam

bda2

k)

; ne

w(C

ontR

atT

oV2)

; ne

w(A

RTP

1);

new

(SR

T1P

1);

new

(SR

T2P

1);

new

(Con

v2);

ne

w(D

ataS

etY

);

new

(Aln

vers

e);

Siz

e D

istr

ibu

tio

n I

nit

iali

sati

on

; C

onta

min

ant

Loc

atio

n In

itia

lisa

tio

n;

Det

erm

ine

Mod

el

Par

amet

ers

fn S

ize;

G

raph

1_In

Tti

alis

e;

--

Rep

eats

:=O

; Fl

ag1

:=0;

P

lot

Var

:=O

; C

onv:

:::va

r:=O

;

Tim

eO A

RT

and

SRTs

; G

uess

::::s

RT

sP1;

-

whi

le

Rep

eats

<It

erat

ion

s do

be

gin whi

le (

Fla

g1=

0) d

o be

gin Cal

e AR

TP1

and

SRTs

P1C

; C

hecK

con

verg

ence

; R

eGue

ss_S

RT

sP1;

en

d;

Plo

t_V

ar:=

Plo

t_V

ar+

1;

new

(Del

taT

_k);

new

(SR

T1P1

C);

new

(SR

T2P1

C);

Page 170: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

06/1

5/19

95

09:4

8 F

ilen

ame:

M

OD

EL5E

1.PA

S Pa

ge

13

end;

if P

lot

Var

=P

rint

C

rit

then

be

gin

--

Plo

t V

ar:=

O;

Con

v-V

ar:=

Con

v V

ar+1

; G

rapn

1 R

esu

lts;

C

ale

Con

vers

ion;

en

d;

-

Upd

ate_

AR

T_a

nd_S

RT

s;

Gue

ss

SRTs

P1;

Fla

g1:=

0;

Rep

eats

:=R

epea

ts+

1;

read

ln(H

ardC

opy)

; if

H

ardC

opy=

1 th

en S

cree

nDum

p(3,

0,2,

1.5

,1.5

,0, 1

,0,e

rro

r);

Cle

arlJ

indo

w;

Gra

ph2_

Init

iali

se_a

nd_D

raw

; re

adln

(Har

dCop

y);

if

Har

dCop

y=1

then

Scr

eenD

umpC

3,0,

2, 1

.5,1

.5,0

,1,0

,err

or)

;

clos

eseg

raph

i cs;

end.

Page 171: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

0/19

95

16:2

7 Fi

lena

me:

M

OD

EL5E

2.PA

S Pa

ge

Prog

ram

Mod

el5E

2;

(Mod

el5E

2.

( *

Thi

s pr

ogra

m

is a

too

l fo

r *

The

prog

ram

cal

cula

tes

the

and

soli

d r

eact

ants

wit

hin

deve

lope

d by

Dix

on.

anal

yzin

g TC

LP d

ata.

}

conc

entr

atio

n p

rofi

le o

f fl

uid

}

( ( ( ( ( ( ( ( ( (

* T

his

prog

ram

onl

y pr

ovid

es

orde

rs.

a p

arti

cle

usin

g th

e eq

uati

ons

as

} } fo

r v

aria

ble

so

lid

rea

ctan

t } }

* A

ssum

ptio

ns

in

this

mod

el

incl

ude:

}

·Th

e s

oli

d r

eact

ant

dep

osi

ts w

ithi

n th

e p

arti

cle

} re

sem

ble

thos

e on

th

e su

rfac

e.

} ·

The

dep

osi

ts w

ould

bot

h re

act

to t

he s

ame

exte

nt

} if

eac

h w

ere

expo

sed

to t

he s

ame

acid

co

nce

ntr

atio

n

} fo

r th

e sa

me

tim

e.

}

(Cod

ed:

Gra

ham

Dav

ies.

}

( D

epar

tmen

t of

Che

mic

al

Eng

inee

ring

. }

( U

nive

rsit

y of

C

ape

Tow

n.

} (

28

Feb

ruar

y 19

95.

} (

29 M

ay

1995

Upd

ated

(G

MO

). }

{···············--········-···········-········--···-~---······-·-····-···}

(Dec

lara

tion

s:

}

uses

crt

,std

hdr,

gj,g

raph

,wor

lddr

,seg

raph

,int

egra

t,M

2C1B

rent

Roo

ts;

cans

t (***

The

se a

re t

he p

aram

eter

s ap

pli

cab

le t

o t

he r

efer

ence

siz

e cl

ass.

**

*}

Bet

a1

Kap

paP1

Ord

SP1

Bet

a2

Kap

paP2

O

rdSP

2

Voi

dage

=10

.0;

=0.

12;

=1.

0;

=0.

0;

=0.

0;

=1.

0;

=0.

01;

(Dim

ensi

onle

ss S

toic

hiom

etri

c ra

tio

def

ined

pg

11

} (R

atio

of

reat

ion

rat

e of

so

lid

rea

ctan

t re

sid

ing

}

(wit

hin

the

par

ticl

e to

por

ous

dif

fusi

on

of

flu

id

} (i

nto

the

par

ticl

e. D

efin

ed p

g 11

D

ixon

. }

{Rea

ctio

n or

der

of

the

soli

d r

eact

ants

wit

hin

the

} ~o~s.

· }

(Voi

dage

of

the

soli

d p

arti

lces

.(P

oro

sity

) }

<***

The

se a

re p

aram

eter

s w

ith

repe

ct

to t

he C

STR

expe

rim

ent.*

****

****

**}

Vol

Liq

=

0.15

9;

(Vol

ume

of

liq

uid

lix

ivia

nt.

(m

3)

Tot

Vol

Par

t=0.

577;

{T

otal

vo

lum

e of

the

so

lid

par

tilc

es.

M

=2;

(Num

ber

of s

ize

clas

ses.

Ref

Si z

eCl

=1;

(Def

ines

th

e re

fere

nce

size

cla

ss.

}

} } }

{***

The

se a

re n

umer

ical

m

etho

d pa

ram

eter

s.**

****

****

****

****

****

****

***}

N

Del

taE

=19;

<H

alf

the

nunb

er o

f in

teri

or

po

ints

. r=

O

and

r=R

} (n

ot

incl

uded

. =

1/(N

+l)

; (S

pace

In

crem

ent.

}

Cal

cula

ted

from

1/

(N+

1).

(Sin

ce}

07/3

0/19

95

16:2

7 F

ilen

ame:

M

OD

EL5E

2.PA

S Pa

ge

2

Del

taT

=

0.00

1;

Nor

m C

rit

=1e

·6;

Con

v C

rit

=1e

·8·

SCon

c To

i =

1e·4

;

Max

lter

=1

00;

lter

atio

ns=

10

0;

Pri

nt

Cri

t=10

; V

iew

S1ze

Cl=

2;

{ R

=i*d

E an

d R

is

at

poin

t N

+1.)

}

{Tim

e In

crem

ent.

{C

onve

rgen

ce c

rite

ria b

ased

on

the

norm

of

ve

ctor

{*

**

{Con

verg

ence

cri

teri

a f

or

the

Bre

nt R

outi

ne.

{Dim

ensi

onle

ss c

on

cen

trat

ion

of

soli

d b

elow

whi

ch

{it

is

ass

umed

to

be

neg

lig

ible

. {M

axim

um

iter

atio

ns

for

the

Bre

nt

Rou

tine

.

{It

erat

ion

s in

ti

me.

{D

eter

min

ed f

rom

des

ired

Pri

nt

Del

ta T

/Del

ta T

{T

he c

on

cen

trat

ion

pro

file

s o

f-th

is s

izec

lass

are

{g

raph

ed

in g

raph

1.

(N

B V

iew

Size

Cl

<= M

.)

} } } } } } } } } } }

(***

Oth

er

info

rmat

ion

requ

ired

.***

****

****

****

****

****

****

****

****

****

*}

Val

idD

ir

=1F:

\TP6

1;{

Val

id d

irec

tory

fo

r gr

aphi

cs d

riv

ers.

}

type

var ar

ray1

= A

rray

[l .•

50,

1 .•

2]

of

Dou

ble;

Arb

lnde

x,S

izel

ndex

,err

or

Rep

eats

,Plo

t_V

ar,C

onv

Var

,Fla

g1,H

ardC

opy

Con

v1,C

onv2

,Dat

aSet

X,D

ataS

etY

,

:In

teg

er;.

Bet

a1

k,B

eta2

k,

Kap

paP1

k,

Kap

pap2

k,

Kap

paS1

k,

Kap

paS2

k

Lam

bda1

k,

Lam

6da2

_k,C

ontR

atio

V1,

Con

tRat

ioV

2'

-

: In

teg

er;

:·ve

ryL

ongV

ecto

r;

:"S

hort

Vec

tor;

Oel

taT

K

AR

T,A

RfP

1,SR

T1,S

RT2

,SR

T1P1

,SR

T2P1

,SR

T1P1

C,S

RT2

P1C

A

Mat

rix,

Aln

vers

e A

RT

P1C

Val

,Sum

Size

Dat

a 2,

NuS

tar

Lam

bda1

,Lam

bda2

,Kap

paS1

,Kap

paS2

G

Lab

el1,

Gla

bel2

Siz

eDat

a:

Arr

ay[1

•• 5

0,1

•• 2

l of

Rea

l;

CART

A

lpha

fn

(r)

at

tim

e T

CA

RTP1

A

lpha

fn

(r)

at

tim

e T+

1 {S

RT1

Sigm

a fn

(r)

at

tim

e T

{S

RTs

P1

Sigm

a fn

(r)

at

tim

e T+

1 (g

uess

ed)

: ·sh

ort

Vec

tor;

:"

Arr

ay1;

sqrM

at;

:·sq

rMat

; :E

xten

ded;

:E

xten

ded;

:S

trin

g;

rang

e O

.. M

0

.• N

+1}

rang

e O

.. M

0

.• N

+1}

rang

e O

•. M

O

.. N

+1}

rang

e 0 .

. M

0 ..

N+1

} {S

RTs

P1C

Si

gma

fn(r

) at

ti

me

T+1

(cal

cula

ted

) ra

nge

O .. M

O

•. N

+1}

{YV

ect

'Con

st'

vec

tor

in C

rank

-Nic

olso

n m

etho

d ra

nge

0 .•

N+1

}

CA

Mat

rix

Mat

rix

of C

rank

-Nic

olso

n co

effi

cien

ts

rang

e N*

N

}

{Dat

aSet

X

X v

ecto

r us

ed

in t

he

grap

hing

ro

uti

ne

rang

e o •

. N+1

}

{·--

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Fun

ctio

n P

ower

(Bas

e,P

ow:r

eal)

:Ext

ende

d;

begi

n if P

ow=O

th

en P

ower

:=1

else

if

Bas

e=O

th

en P

ower

:=O

el

se

.Pow

er:=

expC

Pow

*ln(

base

));

(j

0 Q..

~

~ -· (I} -s· ~

-0 .., ~

0 a.

·~· -· Ul ttj·

N

- .. ~

U:i

•·

Page 172: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

0/19

95

16:2

7 F

ilen

ame:

M

OD

EL5E

2.PA

S Pa

ge

3

end;

{---

----

----

----

----

----

----

----

----

----

----

-·--

----

----

----

----

----

----

--}

Pro

cedu

re S

ize_

Dis

trib

uti

on

_In

itia

lisa

tio

n;

{Thi

s pr

oced

ure

sets

up

the

size

dis

trib

uti

on

dat

a ar

ray

. In

itia

lly

the

}

{Siz

eDat

a ar

ray

con

tain

s ra

dius

in

form

atio

n an

d fr

acti

on

al

volu

me

} {i

nfor

mat

ion

(ie

R a

nd V

p/V

tot)

. On

ou

tput

it

con

tain

s re

lati

ve

radi

us

} {i

nfor

mat

ion

and

rela

tiv

e vo

lum

e in

form

atio

n C

ie R

/R

ref

and

Vp/

Vp

ref)

. }

{Id

eall

y t

his

in

form

atio

n w

ould

be

re

ad

in f

rom

a d

ata

file

. -

}

var R

efR

adiu

s,V

olR

efP

art

:Dou

ble;

begi

n Siz

eDat

a[1,

1J

=11

.35e

-3;

S ze

Dat

a C1

, 21

= 1

/100

S

izeD

ata[

2, 1

l =

11.3

5e-3

; S

zeD

ata

[2, 2

1 =9

9/10

0 S

izeD

ata[

3, 1

l =

O.O

e-3;

S

zeD

ata

[3, 2

1 =

0/1

00

Siz

eDat

a[4,

1l

= O

.Oe-

3;

S ze

Dat

a [4

, 21

= 0

/100

S

izeD

ata[

5,1l

=

O.O

e-3;

, S

zeD

ata

[5, 2

1 =

0/1

00

Siz

eDat

a[6,

1l

= O

.Oe-

3;

S ze

Dat

a [6

, 21

= 0

/100

S

izeD

ata[

7, 1

l =

O.O

e-3;

S

zeD

ata

[7, 2

1 =

0/1

00

Siz

eDat

a[8,

1l

= O

.Oe-

3;

S ze

Dat

a[8,

2l

= 0

/100

=

O.O

e-3;

S

zeD

ata[

9,2l

=

0/1

00

Siz

eDat

a[9,

1l

Siz

eDat

a[10

, 1J

= O

.Oe-

3;

S ze

Dat

a[10

,2l

= 0

/100

Vol

Ref

Par

t:=

Tot

Vol

Par

t*S

izeD

ata[

Ref

Siz

eCl,

21;

Ref

Rad

ius

:=S

izeD

ata[

Ref

Siz

eCl,

11;

Sum

Size

Dat

a_2:

=0;

for

Siz

elnd

ex:=

1 to

M do

be

gin Siz

eDat

a[S

izel

ndex

,1l:

=S

izeD

ataC

Siz

elnd

ex, 1

1/R

efR

adiu

s;

Siz

eDat

a[S

izel

ndex

,2l:

=S

izeD

ata[

Siz

elnd

ex,2

l*T

otV

olP

art/

Vol

Ref

Par

t;

Sum

Siz

eDat

a_2:

=S

umS

izeD

ata_

2+S

izeD

ataC

Siz

elnd

ex,2

l;

end;

NuS

tar:

=V

olL

iq/C

Voi

dage

*Vol

Ref

Par

t);·

{Rat

io o

f vo

lum

e of

bu

lk f

luid

to

flu

id

in p

arti

cle

pore

s.

end;

}

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re C

onta

min

ant_

Loc

atio

n_In

itia

lisa

tion

;

{Thi

s pr

oced

ure

is u

sed

to d

efin

e th

e co

ntam

inan

t ra

tio

vec

tor

(rati

o o

f }

{th

e su

rfac

e co

ntam

inan

t co

nce

ntr

atio

n t

o b

ulk

cont

amin

ant

con

cen

trat

ion

).}

{NO

TE:

If a

ny s

ize

clas

s of

p

arti

cles

hav

e a

surf

ace

con

cen

trat

ion

of

} {

cont

amin

ant,

th

en s

o to

o m

ust

the

refe

renc

e si

ze c

lass

. }

begi

n Con

tRat

ov

1 · C

1l =O

C

ontR

at

ov2·

[11

=O

Con

tRat

oV

1 ·

C2l

=O

Con

tRat

ov

2· [

21

=O

Con

tRat

oV

1 · [

3]

=O

Con

tRat

ov

2 · [

3]

=O

Con

tRat

oV

1 · C

4l =O

C

ontR

at

ov2

· C4l

=O

07/3

0/19

95

16:2

7 F

ilen

ame:

M

OD

EL5E

2.PA

S Pa

ge

4

Con

tRat

ov

1·cs

1 =O

C

ontR

at

oV1"

[6l

=O

Con

tRat

oV

1"[7

] =O

C

ontR

at

oV1"

[8J

=O

Con

tRat

oV

1"[9

] =O

C

ontR

at

oV1"

[10J

=O

Con

tRat

ov

2"[5

] =O

C

ontR

at

ov2"

[6]

=O

Con

tRat

ov

2"[7

] =O

C

ontR

at

ov2"

[8]

=O

Con

tRat

ov

2"[9

J =O

C

ontR

at

ov2"

[10J

=O

en

d;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re D

eter

min

e_M

odel

_Par

amet

ers_

fn_S

ize;

{Thi

s pr

oced

ure

dete

rmin

es

the

mod

el

para

met

ers

each

si

ze c

lass

of

} {

par

ticl

es.

}

var F

lag1

,Fla

g2

:In

teg

er;

begi

n F

lag1

:=0;

F

lag2

:=0;

fo

r S

izel

ndex

:=1

to M

do

begi

n Lam

bda1

k"

CS

izel

ndex

J:=

Con

tRat

ioV

1"C

Siz

elnd

exJ

-/(

1+C

ontR

atio

v1·c

size

lnde

xJ);

La

mbd

a2

k"C

Siz

elnd

exJ:

=C

ontR

atio

V2"

CS

izel

ndex

l -

/(1+

Con

tRat

ioV

2"[S

izel

ndex

J);

if C

ontR

atio

v1·c

size

lnde

xJ<

>O

the

n F

lag1

:=F

lag1

+1;

if

Con

tRat

iov2

·csi

zeln

dexJ

<>

O t

hen

Fla

g2:=

Fla

g2+

1;

end;

if

CC

CFl

ag1=

1)

and

(Con

tRat

ioV

1"[R

efS

izeC

ll=

0))

or

((F

lag2

=1)

an

d (C

ontR

atio

v2"[

Ref

Siz

eCll

=0)

))

then

beg

in

clo

sese

gra

ph

ics;

w

rite

lnC

'Con

tam

inan

t L

ocat

ion

Vio

loat

ion

.');

re

adln

; en

Lam

bda1

=L

ambd

a1

k"[R

efS

izeC

lJ;

Lam

bda2

=

Lam

bda2

-k"[

Ref

Siz

eCll

; K

appa

S1

=Lambda1~KappaP1/C1-Lambda1);

Kap

paS2

=L

ambd

a2*K

appa

P2/C

1-L

ambd

a2);

for

Siz

elnd

ex:=

1 to

M do

be

gin Del

taT

_k-C

Siz

eind

ex, 1

] :=

Del

taT

/Siz

eDat

a[S

izel

ndex

, 1J

/Siz

eDat

a[S

izel

nd

ex,1

J;

Bet

a1

k"[S

izel

ndex

J :=

Bet

a1*C

1+C

ontR

atio

V1"

CR

efSi

zeC

lJ)

-/C

1+C

ontR

atio

V1"

[Siz

elnd

exJ)

; B

eta2

k"[

Siz

elnd

exJ

:=B

eta2

*(1+

Con

tRat

ioV

2"[R

efS

izeC

l])

-/C

1+C

ontR

atio

V2"

[Siz

elnd

ex])

; ·K

appa

P1

k" [

Siz

elnd

exJ

:=K

appa

P1*

Siz

eDat

a[S

izel

ndex

, 11

-*S

izeO

ata[

Siz

elnd

ex,1

J;

Kap

paP2

k"

CS

izel

ndex

J:=

Kap

paP

2*S

izeD

ataC

Siz

elnd

ex,1

J -

*Siz

eDat

a[S

izei

ndex

,11;

if

Con

tRat

ioV

1"C

Size

lnde

xJ=

O

then

Kap

paS

1_k"

[Siz

elnd

exJ

:=O

el

se

Kap

paS1

k"

[Siz

elnd

ex]

:=K

appa

S1*P

ower

((C

ontR

atio

V1"

CSi

zeln

dexJ

-

/Con

tRat

ioV

1"[R

efS

izeC

ll),

Ord

SP

1)

*Siz

eDat

a[S

izel

ndex

,1J;

if

Con

tRat

iov2

· C

Size

lnde

xJ=O

th

en K

appa

S2

k"[S

izel

ndex

J :=

O

else

K

appa

S2_

k"[S

izel

ndex

J :=

Kap

paS

2*P

ower

((C

ontR

atio

V2"

[Siz

elnd

exJ

Page 173: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

0/19

95

16:2

7 Fi

lena

me:

M

OD

EL5E

2.PA

S Pa

ge

5

/Con

tRat

ioV

2"[R

efS

izeC

ll )

,Ord

SP2)

*S

izeD

ata[

Siz

elnd

ex, 1

J;

end·

en

' {-

-'.·

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

-}

Pro

cedu

re T

imeO

_AR

T_an

d_SR

Ts;

{Thi

s pr

oced

ure

uses

th

e in

itia

l co

ndit

ions

to

set

th

e al

pha

and

sigm

a } }

surf

ace}

{v

ecto

rs.

{Not

e th

at A

RT[

N+1

J, A

RTP

1[N

+1],

SRT1

CN+1

J an

d SR

T1P1

[N+1

] ar

e th

e {c

once

ntra

tion

s of

th

e li

qu

id a

nd

soli

d r

eact

ants

.

begi

n for

Siz

elnd

ex:=

1 to

M do

be

gin fo

r A

rbln

dex:

=O

to N

do

begi

n AR

T"[

Size

inde

x,A

rbin

dexJ

=O

S

RT

1"[S

izei

ndex

,Arb

inde

xJ

=1

SR

T2"

[Siz

eind

ex,A

rbin

dexJ

=1

en

AR

T![

Size

inde

x,N

+1J

=1

SRT

1"[S

izei

ndex

,N+

1l

=1

SRT

2"[S

izei

ndex

,N+1

J =1

en

for'

arbi

ndex

:=O

to

max

v do

be

gin·

C

onv1

"[A

rbin

dexJ

:=O

; C

onv2

"[A

rbin

dexJ

:=O

; en

end;

'

}

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re G

uess

_SR

TsP

1;

{Thi

s pr

oced

ure

prov

ides

the

in

itia

l "g

uess

" fo

r th

e it

erat

ion

. It

use

s }

{the

pre

viou

s ti

me

inte

rval

's v

alue

s as

th

e gu

ess.

}

begi

n for

Siz

eind

ex:=

1 to

M do

be

gin fo

r A

rbin

dex:

=O

to (

N+1

) do

be

gin SR

T1P

1"[S

izei

ndex

,Arb

inde

xJ:=

SR

T1"

CS

izei

ndex

,Arb

inde

xJ;

SR

T2P

1"[S

izei

ndex

,Arb

inde

xJ:=

SR

T2"

[Siz

eind

ex,A

rbin

dexl

; en

. A

RT

P1"[

Size

inde

x,N

+1J

:=A

RT

"[Si

zein

dex,

N+

1J;

end·

en

d;

'

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re R

eGue

ss_S

RTs

P1;

{Thi

s pr

oced

ure

prov

ides

an

upda

ted

"gue

ss"

for

the

next

it

erat

ion

. It

{u

ses

the

SRT1

P1C

vect

or a

s th

e up

date

d gu

ess.

begi

n for

Siz

eind

ex:=

1 to

M do

be

gin fo

r A

rbln

dex:

=O

to (

N+1

) do

} }

07/3

0/19

95

16:2

7 F

ilen

ame:

M

OD

EL5E

2.PA

S Pa

ge

6

begi

n SR

T1P

1"[S

izel

ndex

,Arb

lnde

xJ :

=S

RT

1P1C

"[S

izel

ndex

,Arb

lnde

xJ;

SR

T2P

1"[S

izei

ndex

,Arb

inde

xJ :

=S

RT

2P1C

"[S

izei

ndex

,Arb

lnde

xJ;

end·

AR

TP1

· [S

izel

ndex

,N+

1J :=

AR

TP1C

Val

; en

end·

'

{--'

.---

----

----

--J-

----

----

----

----

----

----

----

----

----

----

----

----

----

---}

P

roce

dure

Cal

c_C

rank

_Nic

olso

n_M

atri

x(va

r Y

Vec

tor

:Sho

rtV

ecto

r);

var R

ows,

Col

s : I

nte

ger

;

begi

n for

Row

s:=O

to

(N

+1)

do

begi

n for

Col

s:=O

to

(N

+1)

do

AM

atri

x· [

Row

s,C

olsJ

:=O

; en

d;

AM

atri

x"[0

,0J:

=C

-6-D

elta

E*D

elta

E*S

izeD

ata[

Siz

eind

ex,1

J*S

izeD

ata[

Siz

elnd

ex,1

J *(

Kap

paP1

k"

[Siz

elnd

exJ*

Pow

er(S

RT

1P1"

[Siz

eind

ex,O

J,O

rdS

P1)

+

Kap

paP

2_K

-[S

izel

ndex

]*P

ower

(SR

T2P

1"C

Siz

eind

ex,O

J,O

rdS

P2)

) -2

*Del

taE

*Del

taE

*Siz

eDat

a[S

izel

ndex

, 1J*

Siz

eDat

a[S

izel

ndex

,1J

/Del

taT

_k

-[S

izei

nd

ex,1

J);

AM

atri

x" [

0, 1

] :=

6;

YV

ecto

r[O

J :=

AR

T"[

Siz

eind

ex,O

J*(6

+D

elta

E*D

elta

E*S

izeD

ata[

Siz

eind

ex,1

J *S

izeD

ata[

Siz

eind

ex,1

J*(K

appa

P1

k"[S

izei

ndex

J *P

ower

(SR

T1"

[Siz

elnd

ex,O

J,O

rdS

Pl)

+K

appa

P2

k"[S

izei

ndex

l *P

ower

(SR

T2"

[Siz

elnd

ex,O

J,O

rdS

P2)

) -

-2*D

elta

E*D

elta

E*S

izeD

ata[

Siz

elnd

ex, 1

J *S

izeD

ata[

Siz

elnd

ex,1

]/D

elta

T k

"[S

izei

nd

ex,1

])

-ART

" [S

izel

ndex

, 1]*

6;

-

for

Row

s:=1

to N

-1

do

begi

n AM

atri

x"[R

ows,

Row

s-1]

:=R

ows-

1;

AM

atri

x"[R

ows,

Row

s]

:=-2

*Row

s-R

ows*

Del

taE

*Del

taE

*Siz

eDat

a[S

izei

ndex

, 1]

*Siz

eDat

a[S

izel

ndex

,1J*

(Kap

paP

1 k"

[Siz

eind

exl

*Pow

er(S

RT

1P1"

[Siz

eind

ex,R

owsJ

,Ord

SP

1)

+Kap

paP2

k"

[Siz

elnd

ex]

*Pow

er(S

RT

2P1"

[Siz

eind

ex,R

owsJ

,Ord

SP

2))

-2*R

ows*

Del

taE

*Del

taE

*Siz

eDat

a[S

izel

ndex

, 1l

*Siz

eDat

a[S

izel

ndex

,1]/

Del

taT

k"[

Siz

eind

ex, 1

l;

AM

atri

x"[R

ows,

Row

s+1l

:=R

ows+

1;

-Y

Vec

tor[

Row

sl

:=A

RT

"[Si

zein

dex,

Row

s-1J

*(-R

ows+

1)+

end;

AM

atri

x"[N

,N-1

J:=

N-1

;

AR

T"[

Size

inde

x,R

owsJ

*C2*

Row

s+R

ows*

Del

taE

*Del

taE

*S

izeD

ata[

Siz

elnd

ex,1

J*S

izeD

ata[

Siz

elnd

ex,1

J *C

Kap

paP1

k"

[Siz

elnd

exl

*Pow

er(S

RT

1"[S

izei

ndex

,Row

sJ,O

rdS

P1)

+K

appa

P2

k"[S

izel

ndex

l *P

ower

CSR

T2"

[Siz

elnd

ex,R

owsJ

,Ord

SP2>

> -2

*Row

s*D

elta

E*D

elta

E*S

izeD

ata[

Siz

elnd

ex,1

] *S

izeD

ata[

Siz

elnd

ex,1

J/D

elta

T k

"[S

izel

nd

ex,1

l)

+AR

T"[

Size

lnde

x,R

ows+

1J*C

-Row

s-1)

;

AM

atri

x"[N

,Nl

:=-2

*N-N

*Del

taE

*Del

taE

*Siz

eDat

a[S

izel

ndex

, 1J

*Siz

eDat

a[S

izei

ndex

,1J*

CK

appa

P1

k"[S

izei

ndex

l *P

ower

(SR

T1P

1"[S

izel

ndex

,NJ,

Ord

SP

1)+

Kap

paP

2_k-

[Siz

eind

exl

Page 174: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

0/19

95

16:2

7 Fi

lena

me:

M

ODEL

5E2.P

AS

Page

7

YV

ecto

r[N

J

*Pow

er(S

RT

2P1-

[Siz

eJnd

ex,N

J,O

rdSP

2))-

2*N

*Del

taE

*Del

taE

*S

izeD

ata[

Siz

elnd

ex,1

J*S

izeD

ata[

Siz

elnd

ex,1

l /D

elta

T

k·cs

izel

ndex

, 1l;

:=

AR

T-[

Size

lnde

x,N

-1J*

(-N

+1)+

AR

T-[

Size

lnde

x,N

l*C

2*N

+ N

*Del

taE

*Del

taE

*Siz

eDat

a[S

izel

ndex

, 1l

*Siz

eDat

a[S

izel

ndex

, 1J*

CK

appa

P1

k-[S

izel

ndex

l *P

ower

CSR

T1-

[Siz

elnd

ex,N

J,O

rdSP

l)+K

appa

P2

k·cs

izel

ndex

J *P

ower

(SR

T2-

[Siz

elnd

ex,N

l ,O

rdSP

2))-

2*N

*DeT

taE

*Del

taE

*S

izeD

ata[

Siz

elnd

ex,1

l*S

izeD

ata[

Siz

elnd

ex,1

l /D

elta

T

k·cs

izel

ndex

, 1l )

+AR

T-[

Size

lnde

x,N

+ll*

C-N

-1>

-AR

TP1

.[Siz

eJnd

ex,N

+1J*

CN

+1);

end;

{--

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

---}

P

roce

dure

Cal

c_A

RTP

1_an

d_SR

TsP1

C;

var M

assB

alV

al,A

Mat

Det

V

alue

AtR

oot

Out

putV

ecto

r,Y

Vec

tor

Dou

ble;

R

eal;

S

hort

Vec

tor;

begi

n .

{F

irst

cal

cula

te t

he A

RTP1

v

ecto

rs.

}

for

Siz

elnd

ex:=

1 to

M do

be

gin Cal

e C

rank

N

icol

son

Mat

rixC

YV

ecto

r);

Gau

ssJo

rdan

(AM

atri

xT,Y

Vec

tor,

CN

+1)

,0ut

putV

ecto

r,A

lnve

rse·

,AM

atD

et);

fo

r A

rbln

dex:

=O

to N

do

ART

P1. [

Siz

elnd

ex,A

rbln

dexl

:=

Out

putV

ecto

r[A

rbJn

dexl

;

end;

{The

Gau

ssJo

rdan

pro

cedu

re c

alcu

late

s va

lues

fo

r th

e AR

T ve

ctor

fro

m

{poi

nt 0

to

poin

t N

(al

thou

gh

it m

akes

us

e of

th

e N+

1 th

po

int)

. To

{d

eter

min

e th

e N+

1 th

po

int

valu

e,

mak

e us

e of

th

e m

ass

bala

nce

of

(flu

id r

eact

ant

in-t

he

CSTR

.

Mas

sBal

Val

:=O

;

for

Siz

elnd

ex:=

1 to

M do

be

gin

} } } }

Mas

sBal

Val

:=M

assB

alV

al-S

izeD

ata[

Siz

elnd

ex,2

J/2*

(Kap

paS

1_k-

[Siz

elnd

exl

*SR

T1-

[Siz

elnd

ex,(

N+

1)J*

AR

T.[

Size

lnde

x,C

N+

1)J

end;

+Kap

paS1

csiz

elnd

exl*

SR

T1P

1.[S

izel

ndex

,CN

+1)

J *A

RT

P1-[

Size

lnde

x,C

N+1

)J+K

appa

S2

k·cs

izel

ndex

l *S

RT

2.[S

izel

ndex

,CN

+1)

J*A

RT

·csi

zeln

dex,

(N+

1)l

+Kap

paS2

csiz

elnd

exJ*

SR

T2P

1.[S

izel

ndex

,CN

+1)

l *A

RTP1

-[S

izel

ndex

,CN

+1)

J)-3

*Siz

eDat

a[S

izel

ndex

,2l

/(S

izeD

ata[

Siz

elnd

ex,1

J*S

izeD

ata[

Siz

elnd

ex, 1

J)/2

*C

CA

RT

-[Si

zeln

dex,

CN

+1)J

+AR

TP1

·csi

zeln

dex,

CN

+1)J

) -C

AR

T.[

Siz

elnd

ex,N

J+A

RT

P1.

[Siz

elnd

ex,N

J))/

Del

taE

;

AR

TP1

CV

al:=

AR

T.[1

,CN

+1)J

+Del

taT

/NuS

tar*

Mas

sBal

Val

;

{Cal

cula

te t

he S

RTsP

1C

vec

tors

. C

ode

mak

es

use

of

Bre

nt'

s M

etho

d <C

A no

n-li

near

roo

t fi

ndin

g pr

oced

ure)

to

sol

ve f

or

the

roo

t.

} }

07/3

0/19

95

16:2

7 F

ilen

ame:

M

OD

EL5E

2.PA

S Pa

ge

8

for

Siz

elnd

ex:=

1 to

M do

be

gin fo

r A

rbln

dex:

=O

to C

N+1

) do

be

gin

ex, 1

J,

if

(Kap

paP

1_k.

[Siz

elnd

exJ=

0)

then

SR

T1P

1C-[

Siz

elnd

ex,A

rbln

dex]

:=O

els

e be

gin if O

rdSP

1=1

then

be

gin

end SR

T1P1

c· [

Siz

elnd

ex,A

rbln

dexJ

:=S

RT

1.[S

izel

ndex

,Arb

lnde

xJ

*(1-

Del

taT

csiz

elnd

ex,1

J*K

appa

P1

k·c

size

lnd

exl

*Bet

a1

k·cs

izel

ndex

J*A

RT

.[S

izel

ndex

,Arb

lnde

xl

/C2*

C1

7La

mbd

a1

k·c

size

lnd

exJ)

))/(

1+

Del

taT

k

·csi

zeln

dex

, 1J

*Kap

paP

1_k.

[Siz

elnd

exJ*

Bet

a1_k

.[S

izel

ndex

] *A

RT

P1.

[Siz

elnd

ex,A

rbln

dexl

/C2*

C1-

Lam

bda1

_k.[

Siz

elnd

ex])

))

else

if

s'R

T 1P

1 ·[

Si z

el n

dex,

Arb

l nde

xl <

SCon

c_To

l th

en

SR

T1P

1c·c

size

lnde

x,A

rbln

dexJ

:=S

RT

1P1·

csiz

elnd

ex,A

rbln

dexJ

el

se

begi

n ,

SR

T1P

1C.[

Siz

elnd

ex,A

rbln

dexJ

:=B

rent

Roo

ts(0

.0,1

.0,D

:lta

T_k

-[S

izel

nd

Kap

paP1

csiz

elnd

exJ,

Bet

a1

k·c

size

lnd

exJ,

L

ambd

a1-k

·csi

zeln

dexJ

,Ord

SP

l,A

RT

.[S

izel

ndex

,Arb

lnde

xJ,

AR

TP

1·cs

izel

ndex

,Arb

Jnde

xJ,S

RT

1.[S

izel

ndex

,Arb

lnde

xl,

le-8

,100

,Val

ueA

tRoo

t,er

ror)

; en

end·

'

if ~K

appa

P2_k

.[Si

zeln

dexJ

=0)

then

SR

T2P

1C-[

Siz

elnd

ex,A

rbln

dexJ

:=O

els

e be

gin if O

rdSP

2=1

then

be

gin

end S

RT

2P1c

·csi

zeln

dex,

Arb

lnde

xJ:=

SR

T2.

[Siz

elnd

ex,A

rbln

dexJ

*C

1-D

elta

T

k·cs

izel

ndex

,1J*

Kap

paP

2 k·

csiz

elnd

exl

*Bet

a2 k

·csi

zeln

dexl

*AR

T·c

size

lnde

x,A

rbln

dexl

/C

2*C

17

Lam

bda2

k

·csi

zeln

dex

J)))

/(1

+D

elta

T k

·csi

zeln

dex

, 1J

*Kap

paP

2_k.

[Siz

elnd

exJ*

Bet

a2_k

·csi

zeln

dex]

*A

RT

P1-

[Siz

elnd

ex,A

rbln

dex]

/(2*

C1-

Lam

bda2

_k.[

Siz

elnd

exJ)

))

else

if

SR

T2P

1-[S

izel

ndex

,Arb

lnde

x]<

SC

onc

Tol

th

en

SR

T1P

1c·c

size

lnde

x,A

rbln

dexJ

:=S

RT

2P1·

csiz

elnd

ex,A

rbln

dexJ

el

se

begi

n SR

T2P

1C.[

Siz

elnd

ex,A

rbln

dexJ

:=B

rent

Roo

ts(O

.O, 1

.0,

Del

taT

csiz

elnd

ex,1

J,K

appa

P2

k·c

size

lnd

exJ,

B

eta2

K·c

size

lnde

x],L

ambd

a2 k

·csi

zeln

dexl

,Ord

SP

2,

AR

T.[

Siz

elnd

ex,A

rbln

dexl

,AR

iP1.

[Siz

elnd

ex,A

rbln

dexJ

,

end·

en

' en

' en

' en

d;

'

SR

T2.

[Siz

elnd

ex,A

rbln

dexJ

,1e-

8,10

0,V

alue

AtR

oot,

erro

r);

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re C

heck

_Con

verg

ence

;

{Thi

s pr

oced

ure

chec

ks w

heth

er o

r no

t th

e so

luti

on

has

con

verg

ed b

y }

Page 175: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

0/19

95

16:2

7 F

ilen

ame:

M

OD

EL5E

2.PA

S Pa

ge

9

{com

pari

ng

the

gues

sed

valu

e of

SR

T1P1

w

ith

a ca

lcu

late

d v

alue

of

SRT1

P1.

} {A

lso

com

pare

s th

e ca

lcu

late

d v

alue

of

ARTP

1C

with

gu

esse

d va

lue

of

} {A

RTP

1.

}

var N

orm

1,N

orm

2,N

orm

3

begi

n

:Dou

ble;

Nor

m1

=O;

{Usi

ng a

nor

m *

**

} N

orm

2 =O

· N

orm

3 =O

'. fo

r S

zein

dex:

=1

to M

do

begi

n for

Arb

lnde

x:=O

to

(N

+1)

do

begi

n if (

Bet

a1

k"[S

izel

ndex

]<>

O)

and

(Kap

paP1

. k"

[Siz

elnd

exl<

>O

) th

en b

egin

N

orm

1::N

orm

1+C

SRT

1P1C

"[Si

zeln

dex,

Arb

inde

xl

·SR

T1P

1"[S

izel

ndex

,Arb

lnde

x])*

(SR

T1P

1C.[

Siz

elnd

ex,A

rbln

dexl

·S

RT

1P1"

[Siz

elnd

ex,A

rbln

dexJ

);

end

,els

e N

orm

1 :=

O;

if (

Bet

a2_k

"[S

izel

ndex

l<>

0)

and

(Kap

paP2

k"

[Siz

elnd

ex]<

>O

) th

en b

egin

N

orm

2:=N

orm

2+(S

RT

2P1C

"[Si

zeln

dex,

Arb

lnde

xl

-SR

T2P

1"[S

izel

ndex

,Arb

lnde

x])*

(SR

T1P

1C"

[Siz

elnd

ex,A

rbln

dexl

-S

RT

2P1"

[Siz

elnd

ex,A

rbln

dexl

);

end

else

Nor

m2:

=0;

end·

en

' Nor~:=(ARTP1CVal·ART

P1"(

1,N+

1])*

(ART

P1CV

al·A

RTP1

"[1,

N+1l

);

if

(Nor

m1<

Nor

m C

rit)

and

(N

orm

2<N

orm

Cri

t) a

nd

(Nor

m3<

Nor

m C

rit)

th

en F

lag1

::1;

-

-en

d;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re U

pdat

e_A

RT_

and_

SRTs

;

{Thi

s procedu~e

upda

tes

the

alph

a an

d si

gma

vect

ors

for

the

next

it

erat

ion

}

{by

repl

acin

g th

eir

com

pone

nts

wit

h th

e al

phaT

+1

and

sigm

aT+1

v

ecto

rs.

}

begi

n for

Siz

elnd

ex:=

1 to

M do

be

gin fo

r A

rbln

dex:

=O

to C

N+1

) do

be

gin AR

T"[

Siz

elnd

ex,A

rbln

dexl

=

AR

TP

1"[S

izel

ndex

,Arb

inde

xl;

SR

T1"

[Siz

elnd

ex,A

rbln

dexl

=

SR

T1P

1"[S

izel

ndex

,Arb

lnde

xl;

SR

T2"

[Siz

elnd

ex,A

rbln

dexl

=

SR

T2P

1"[S

izel

ndex

,Arb

inde

xl;

end·

~d·

, ~d;

,

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re C

alc_

Con

vers

ion;

{Thi

s pr

oced

ure

calc

ula

tes

the

frac

tio

nal

co

nver

sion

of

the

par

ticl

e fo

r }

{th

e ti

me

inte

rval

. It

use

s th

e fo

rmul

a on

pg.

13

Dix

on.

The

inte

gra

tor

} {

is t

he Q

uinn

-Cur

tis

vect

or

inte

gra

tor.

}

07/3

0/19

95

16:2

7 F

ilen

ame:

M

OD

EL5E

2.PA

S Pa

ge

10

var ln

terG

1,ln

terG

2 ln

tegV

al,C

onve

rsio

n :V

eryL

ongV

ecto

r;

:Rea

l;

begi

n for

Siz

elnd

ex:=

1 to

M do

be

gin if K

appa

P1

k"[S

izel

ndex

l<>

O

then

be

gin

-fo

r A

rbln

dex:

=O

to C

N+1

) do

ln

terG

1[A

rbln

dex]

:=

(1-S

RT

1"[S

izel

ndex

,Arb

lnde

xJ)*

Arb

lnde

x*D

elta

E

*Arb

lnde

x*D

elta

E;

lnte

gra

teV

ecto

r(Jn

terG

1,D

elta

E,0

,(N

+1

),ln

teg

Val

);

Con

vers

ion

:=3*

(1-L

ambd

a1

k"[S

izel

ndex

J)*l

nteg

Val

+

Lam

bda1

_k-[

Siz

elnd

ex]*

(1-S

RT

1" [

Siz

elnd

ex,N

+1l

);

Con

v1"(

Con

v V

ar]

:=C

onv1

"[C

onv

Var

J+C

onve

rsio

n*S

izeD

ata[

Siz

elnd

ex,2

] -

/Sum

Size

Dat

a_2;

. e

nd;

if K

appa

P2

k"[S

izel

ndex

l<>

O

then

be

gin

-;

for

Arb

lnde

x:=O

to

(N

+1)

do

lnte

rG2C

Arb

lnde

xJ:=

(1·S

RT

2"[S

izel

ndex

,Arb

lnde

xJ)*

Arb

lnde

x*D

elta

E

*Arb

lnde

x*D

elta

E;

lnte

gra

teV

ecto

r(ln

terG

2,D

elta

E,0

,(N

+1

),ln

teg

Val

);

Con

vers

ion

:=3*

(1-L

ambd

a2

k"[S

izel

ndex

J)*l

nteg

Val

+L

ambd

a2

k"[S

izel

ndex

]*(1

-SR

T2"

[Siz

elnd

ex,N

+1l

);

Con

v2"[

Con

v_V

arJ:

=C

onv2

"[C

onv_

Var

J+C

onve

rsio

n*S

izeD

ata[

Siz

elnd

ex,2

J

end·

en

' en

d;

'

/Sun

Siz

eDat

a_2;

{----------------------------------------------~--------------------------}

Pro

cedu

re G

rap

h1

_1

nit

iali

se;

var B

eta1

S,K

appa

P1S,

Lam

bda1

S,G

DT

S B

eta2

S,K

appa

P2S,

Lam

bda2

S V

iew

Size

ClS

begi

n init

SE

Gra

phic

s(V

alid

Dir

);

Set

Cur

rent

Win

dow

(2);

B

orde

rCur

rent

Win

dow

(1);

S

etA

xesT

ype(

0,0)

; S

cale

Plo

tAre

a(0

.0,0

.0,1

.0,1

.0);

S

etX

Yln

terc

epts

(0.0

,0.0

);

Set

Col

or(2

);

Dra

wX

Axi

s(0.

2,1>

; D

raw

YA

xis(

o.2 61>

; L

abel

XA

xis(

1,

);

Lab

elY

Axi

s(1,

0);

Tit

leX

Axi

s('D

imen

sion

less

Rad

ius'

);

Tit

leY

Axi

s('D

imen

sion

less

Con

cent

rati

on'>

; T

itle

Win

dow

('Mod

el5E

2'>

; S

tr(B

eta1

k"

CV

iew

size

Cll

:6:3

,Bet

a1S

);

Str

(Kap

paP

1_k"

[Vie

wS

izeC

lJ:6

:3,K

appa

P1S

);

stri

ng

st

rin

g

stri

ng

Page 176: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

0/19

95

16:2

7 F

ilen

ame:

M

OD

EL5E

2.PA

S Pa

ge

11

Str

((D

elta

T*P

rint

Cri

t):6

:4,G

DT

S);

St

r(L

ambd

a1

k"C

Vie

wSi

zeC

lJ:5

:3,L

ambd

a1S)

; S

tr(B

eta2

k~CViewSizeClJ:6:3,Beta2S);

Str

(Kap

paP

2_k"

CV

iew

Siz

eClJ

:6:3

,Kap

paP

2S);

St

r(L

ambd

a2

k"C

Vie

wS

izeC

ll:5

:3,L

ambd

a2S

);

Str

(Vie

wS

izeC

l:2,

Vie

wS

izeC

lS);

G

labe

l1:=

Con

cat(

' B

eta1

',

Bet

a1S

,';

Kap

pa1

',Kap

paP

1S,';

La

mbd

a1

Lam

bda1

S,';

GOT

wrt

R

efS

izeC

lass

',G

DT

S);

Gla

bel2

:=C

onca

t('

Bet

a2

',Bet

a2S

, ';

K

appa

2 ',K

appa

P2S

,';

Lam

bda2

L

ambd

a2S,

'; V

iew

Cla

ss

',Vie

wS

izeC

lS);

L

abel

Gra

phW

indo

wC

1,93

0,G

labe

l1,0

,0);

L

abel

Gra

phW

indo

wC

1,90

0,G

labe

l2,0

,0);

en

d;

{····

-·--

----

----

----

----

----

----

·---

----

----

----

----

----

----

----

----

----

-}

Pro

cedu

re G

raph

1_R

esul

ts;

begi

n if V

iew

Size

Cl>

M

then

be

gin Clo

sese

grap

hics

; w

rite

ln('

Gra

ph 1

Dra

w

ERR

OR

');

wri

teln

C'Y

ou h

ave

inst

uct

ed t

he G

raph

ing

Rou

tine

to

gra

ph

the

con

ver

sio

n')

;

wri

teln

C'c

urve

s of

a s

ize

clas

s w

hich

do

es

not

ex

ist.

');

wri

teln

C'R

espe

cify

= V

iew

Siz

eCla

ss

in D

ecla

rati

ons

sect

ion

'>;

read

ln;

end·

Siz~Index:=ViewSizeCl;

for

Arb

inde

x:=O

to

CN

+1)

do D

ataS

etX

"[A

rbln

dexl

:=

Arb

inde

x*D

elta

E;

if K

appa

P1

k"[S

izel

ndex

l<>

O

then

beg

in

for

Arb

Tnde

x:=O

to

CN

+1)

do

Dat

aSet

Y"[

Arb

lnde

xl :=

AR

TP1-

[Siz

elnd

ex,A

rbln

dexl

; L

ineP

lotD

ata(

Oat

aSet

X",

Dat

aSet

Y-,

CN

+2)

,3,0

);

for

Arb

lnde

x:=O

to

(N

+1)

do

Dat

aSet

Y"[

Arb

lnde

xl :

=S

RT

1P1"

[Siz

elnd

ex,A

rbln

dexl

; L

ineP

lotD

ata(

Dat

aSet

X"

,Dat

aSet

Y"

,(N

+2)

,5, 1

);

end·

if

K

appa

P2

k"C

Size

lnde

xJ<>

O

then

beg

in

for

Arb

Tnde

x:=O

to

CN

+1)

do

Dat

aSet

Y"C

Arb

inde

xJ:=

AR

TP1

"CSi

zeln

dex,

Arb

lnde

xJ;

Lin

ePlo

tDat

a(O

ataS

etX

" ,D

ataS

etv·

,CN

+2)

,3,1

);

for

Arb

lnde

x:=O

to

CN

+1)

do

Dat

aSet

Y"[

Arb

lnde

xJ:=

SR

T2P

1"C

Siz

elnd

ex,A

rbln

dexl

; L

ineP

lotD

ata(

Oat

aSet

X",

Dat

aSet

Y",

CN

+2)

,4,2

);

end;

end;

{---

------

----

----

:·--

-~--

----

----

----

----

----

----

------------------------}

Pro

cedu

re G

raph

2_In

itia

lise

_and

_Dra

w;

var X

Axi

sMax

begi

n SetC

urre

ntW

indo

wC

2);

:Rea

l;

07/3

0/19

95

16:2

7 F

ilen

ame:

M

OD

EL5E

2.PA

S Pa

ge

12

Bor

derC

urre

ntW

indo

w(1

);

Set

Axe

sTyp

eC0,

0);

XA

xisM

ax:=

5;

(**

**

*o

r D

elta

T*R

epea

ts;*

***)

S

cale

Plo

tAre

a(0.

0,0.

0,X

Axi

sMax

, 1.0

);

Set

XY

lnte

rcep

ts(0

.0,0

.0);

S

etC

olor

C2)

; D

raw

XA

xisC

CX

Axi

sMax

/5),

1>;

·ora

wY

Axi

s(0.

2, 1

>;

Lab

elX

Axi

sC1,

0);

Lab

elY

Axi

sC1,

0);

Tit

leX

Axi

s('D

imen

sion

less

Rea

ctio

n Ti

me

CWRT

R

efer

ence

Part

icle

)');

T

itle

YA

xisC

'Fra

ctio

nal

Co

nv

ersi

on

');

Tit

leW

indo

w('

Mod

el5E

2');

L

abel

Gra

phW

indo

wC

1,93

0,G

Lab

el1,

0,0)

; L

abel

Gra

phW

indo

wC

1,90

0,G

labe

l2,0

,0);

if

Kap

paP1

k"

[Siz

elnd

exl<

>O

the

n be

gin

for

Arb

Tnd

ex:=

O

to C

onv

Var

do

be

gin

Dat

aSet

X"[

Arb

lnde

xl:=

Arb

lnde

x*P

rint

_Cri

t*D

elta

T;

Dat

aSet

Y"C

Arb

lnde

xl:=

Con

v1"C

Arb

lnde

xJ;

end·

Da

t~Se

tY"[

Ol :=

O;

Lin

ePlo

tDat

a(D

ataS

etX

",D

ataS

etY

-,C

onv_

Var

,5,0

);

end·

if

Kap

paP2

k"

[Siz

elnd

exJ<

>O

th

en b

egin

fo

r A

rbT

ndex

:=O

to

Con

v V

ar d

o be

gin

Dat

aSet

X"[

Arb

lnde

xl:=

Arb

lnde

x*P

rint

C

rit*

Del

taT

; D

ataS

etY

"CA

rbin

dexJ

:=C

onv2

"[A

rbin

dexJ

; en

Dat~SetY"COl :=

O;

Lin

ePlo

tDat

a(D

ataS

etX

",D

ataS

etv·

,con

v_V

ar,4

,0);

en

d;

end;

{··:

·---

----

----

----

----

----

----

----

----

----

----

----

----

-be

gin

----

----

----

----

-}

new

(Bet

a1

k);

new

(Kap

paP1

_k>;

ne

w(K

appa

S1_k

>;

new

(lam

bda1

k

);

new

(Con

tRat

ToV

1);

new

CA

RT)

; ne

w(S

RT

1);

new

(SR

T2)

; ne

w(C

onv1

);

new

(Dat

aSet

X);

ne

w(A

Mat

rix)

;

cl r

scr;

new

(Bet

a2

k);

ne

w(K

appa

P2_k

);

new

(Kap

paS2

_k);

ne

w(L

ambd

a2

k);

new

(Con

tRat

ToV

2);

new

(AR

TP1)

; ne

w(S

RT

1P1)

; ne

w(S

RT

2P1)

; ne

w(C

onv2

);

new

(Dat

aSet

Y);

ne

wC

Ain

vers

e);

Siz

e D

str

ibu

tio

n I

nit

iali

sati

on

; C

onta

m n

ant

Loc

atio

n In

itia

lisa

tio

n;

Det

erm

ne

Mod

el

Par

amet

ers

fn S

ize;

G

raph

1_In

Tti

alis

e;

--

Rep

eats

:=O

; Fl

ag1

:=O

; P

lot

Var

:=O

; Co

n.v:

::va r

: =O

;

new

(Del

taT

_k);

new

(SR

T1P

1C);

new

(SR

T2P

1C);

Page 177: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

0/19

95

16:2

7 F

ilen

ame:

M

OD

EL5E

2.PA

S Pa

ge

13

Tim

eO A

RT

and

SRTs

; G

uess

:::sR

TsP

1;-

whi

le

Rep

eats

<Jt

erat

ions

do

begi

n whi

le (

Fla

g1=

0)

do

begi

n Cal

e AR

TP1

and

SRTs

P1C

; C

hecK

Con

verg

ence

; R

eGiJe

ss S

RTs

P1;

end;

-

Plo

t_V

ar:=

Plo

t_V

ar+

1;

if P

lot

Var

=P

rint

C

rit

then

be

gin

--

Plo

t V

ar:=

O;

Con

v-V

ar:=

Con

v V

ar+1

; G

rapl

l1

Res

ult

s;

Cal

e co

nver

sion

; en

d;

-

Upd

ate

ART

and

SRTs

; G

uess

SR

TsP1

; -

Fla

g1:=

0;

· R

epea

ts:=

Rep

eats

+1;

end;

read

ln(H

ardC

opy)

; if

Har

dCop

y=1

then

Scr

eenD

ump(

3,0,

2, 1

.5,1

.5,0

,1,0

,err

or)

;

Cle

arW

indo

w;

Gra

ph2_

Init

iali

se_a

nd_D

raw

; re

adln

CH

ardC

opy)

; if

H

ardC

opy=

1 th

en S

cree

nD

um

p(3

,0,2

,1.5

,1.5

,0,1

,0,e

rro

r);

cl o

sese

grap

h i c

s;

end.

Page 178: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

Sta

rt.

Initi

alis

e va

rious

var

iabl

es.

Initi

alis

e th

e S

ize

Dis

trib

utio

n.

Initi

alis

e C

onta

min

ant

Loca

tion.

Initi

alis

e S

uper

ficia

l V

eloc

ity F

ile.

Initi

alis

e C

olum

n C

ondi

tions

. In

itial

ise

Par

ticle

Con

ditio

ns.

Gen

erat

e U

nit

Hea

p F

iles.

Det

erm

ine

appr

opri

ate

step

siz

es f

n(si

ze).

Itera

te i

n Ti

me.

Det

erm

ine

the

appr

opria

te D

elta

T.

Itera

te i

n U

nit

Hea

ps.

Rea

d U

nit

Hea

p V

ecto

rs f

rom

Uni

t H

eap

File

.

Cho

ose

ap

pro

pri

ate

ste

p sr

ze t

or

unit

heap

cal

cula

tions

.

Det

erm

ine

Del

ta T

fn(

size

).

Exe

cute

Uni

t6.

(Equ

iv.

CS

TR

mod

el.)

~ ~~

I>

-("'

) 0

-=

c:

g. U

pd

ate

Hea

p C

onve

rsio

n, H

eap

Vec

tors

1=-

• ~

(3\

~

and

Writ

e U

nit

Hea

p R

esul

ts t

o F

ile.

§ 8..

>;

=

(1)

~

'h..

_

:::3

'"O

""'"

>

; •

Incr

em

en

t H

ea

p V

ect

ors

ana-

1 6

9 ~

Bre

akt

hro

ug

h V

ect

ors

. 15;

g

<

~

0 V

l •

::r

>;

·Wri

te c

on

vers

ion

s to

a f

ile. I

1; ?

' g-

s= ~

0 ("'

)• Q

..

. ""

l 0

c.. =

:;;

: 3

~ ~

Gra

ph

Bre

akt

hro

ug

h C

urv

es.

I

' lo

~

~ c"

~

~ C

l=

0:::

>;

I-lo

E

nd

. I

1("1

g

~

s· >

2:::

Dl (I

J

O'

~ ~

>;

= -·

...... c..

~

g == ~

~ o

a ~

c..

8 ~

fllO

I (J

Q

........

(1)

~ =

g

Cl

Q..

~ N

Q

~Cl

Z'

(IJ

Q

3 •

Q..

~ ~

~ :s.

I=' g.

"'1

Page 179: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

1/19

95

08:2

7 F

ilen

ame:

M

OD

EL6C

1.PA

S Pa

ge

1

Prog

ram

Mod

el6C

1;

(Mod

el6C

1.

( ( ( { (

*Thi

s pr

ogra

m

is a

cod

e fo

r he

ap

leac

hing

an

aly

sis.

*I

ncor

pora

tes

unst

eady

sta

te f

low

. *U

ses

Uni

t6C

1 w

hich

is

a m

odi.t

ied

form

of

th

e ch

emic

al

CSTR

m

odel

. *M

odel

6C1

val

id f

or

firs

t or

der

kin

etic

s,

use

Mod

el6C

2 fo

r v

aria

ble

ord

er

kin

etic

s.

} } } } } )

(Cod

ed:

Gra

ham

Dav

i es.

)

( D

epar

tmen

t of

C

hem

ical

E

ngin

eeri

ng.

) (

Uni

vers

ity

of

Cap

e To

wn.

}

( 6

Mar

ch

1995

. }

{ 6

June

19

95.

Upd

ated

. (G

MO)

}

(===

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

==}

{Dec

lara

tion

s:

}

uses

crt

,std

hdr,

gj,g

raph

,wor

lddr

,seg

raph

,int

egra

t,M

2C1B

rent

Roo

ts,U

nit6

C1;

cons

t

var {*

**T

hese

are

the

par

amet

ers

app

liab

le t

o th

e co

lum

n.**

****

****

****

****

}

Col

Len

gth

=1.

76;

(Col

umn

leng

th.

(m)

} C

olV

oida

ge =

0.49

8;

(Voi

dage

of

the

colu

mn.

}

Sat

Fra

c ~0.361;

(Fra

ctio

n o

f th

e vo

id s

pace

fil

led

wit

h fl

uid

. }

(Ass

umed

to

be

cons

tant

in

ti

me.

ie

Doe

s no

t ch

ange

} {w

ith

a ch

ange

in

the

f lo

wra

te.

} G

lobU

etFa

c =

1.0;

{G

loba

l w

etti

ng f

acto

rs o

f th

e p

arti

cles

. }

{***

The

se a

re c

olum

n nu

mer

ical

m

etho

d pa

ram

eter

s.**

****

****

****

****

****

}

NoU

ni tH

eaps

=5;

{Num

ber

of

un

it h

eaps

. }

Col

Del

taE

=1

/NoU

nitH

eaps

;

uSta

r =

1/86

400;

(Ref

eren

ce s

up

erfi

cial

v

elo

city

. E

quiv

alen

t to

1m

· }

{in

24

hour

s.

}

Spe

cCol

lter

s=1;

GfM

ax X

Gf

Hax:

::Y

=1.

0;

=1.

0;

{Max

imum

x-v

alue

fo

r co

nver

sion

gra

phs.

{H

axin

um y

-val

ue f

or

conv

ersi

on g

raph

s.

} }

{***

Oth

er

info

rmat

ion

requ

ired

.***

****

****

****

****

****

****

****

****

****

)

Val

ici'.

>ir

='F:

\TP6

\HO

DE

L6

1;C

Val

id d

irec

tory

fo

r gr

aphi

cs d

riv

ers.

}

{***

****

****

****

****

****

****

****

****

****

****

****

****

****

****

****

****

**}

supV

elfi

le

SupV

elD

ata

11.a

tchS

i zeD

T

Tex

t;

arra

y[1

.. 2

,1 .

• 2]

of D

oubl

e;

arra

y[1

•. m

axcJ

of

In

teg

er;

lntl

engt

hCri

t,In

tLen

gth,

Col

Del

ta_t

,Col

Del

taT

,Arb

Val

ue

Hol

dCon

v1,H

oldC

onv2

N

umSu

bint

,Tim

eCou

nter

Dou

ble;

D

oubl

e;

Inte

ger

;

07/3

1/19

95

08:2

7 F

ilen

ame:

M

ODEL

6C1.P

AS

Page

Co

nti

nu

e,C

oli

ters

AR

TBTC

,SR

T1B

TC,S

RT2

BTC

,Tot

Hea

pCon

v1,T

otH

eapC

onv2

T

imeV

ecto

r T

otH

eapA

RT

Vec

,Tot

Hea

pSol

SRT

1Vec

,Tot

Hea

pSol

SRT

2Vec

OT

fo

r W

atch

Size

co

nvR

esul

ts

:In

teg

er;

"Ver

yLon

gVec

tor;

·v

eryL

ongV

ecto

r;

"Sho

rtve

ctor

"Sqr

Mat

; T

ext;

<===

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

==}

Pro

cedu

re

Init

iali

se_

Var

iou

s_V

aria

ble

s;

begi

n Vol

Liq

T

otV

olP

art

:=C

olD

elta

E*C

olV

oida

ge*C

olL

engt

h*S

atF

rac;

:=

Col

Oel

taE

*(1-

Col

Voi

dage

)*C

olle

ngth

*Glo

bWet

fac;

Cum

Tim

e =O

; U

nitH

eapC

onv1

=O

; U

nitH

eapC

onv2

=O

; C

oli

ters

=O

; T

imeV

ecto

r"[O

J =O

; en

d;

(---

----

----

----

----

----

----

----

·-··

···-

··--

····

·---

-···

-···

····

····

····

··}

P

roce

dure

ln

itia

lise

_S

up

erfi

cial

_V

elo

city

_F

ile;

begi

n assi

gn(S

upV

elF

ile,

'Sup

Vel

Fi.

Dat

');

rese

t(S

upV

elF

ile)

; Su

pVel

Dat

aC1,

1l:=

O;

SupV

elD

ata[

112J

:=O

; re

ad(S

upV

elF

1le,

Sup

Vel

Dat

aC2,

1J>

; re

ad(S

upV

elF

ile,

Sup

Vel

Dat

a[2,

2J>

; In

tlen

gthC

rit:

=C

olV

oida

ge*C

olD

elta

E*C

olle

ngth

; en

d;

(---

----

-·--

-·-·

----

---·

·-·-

·-···

····-

----

----

·---

----

----

-·-·

----

---·

----

) P

roce

dure

Co

l_In

itia

l_C

on

dit

ion

s;

begi

n for

Arb

lnde

x:=O

to

max

c do

be

gin Tot

Hea

pAR

TV

ec"[

Arb

lnde

xJ

=O

Tot

Hea

pSol

SRT

1Vec

"[A

rbin

dexJ

=O

T

otH

eapS

olSR

T2V

ec"[

Arb

inde

xJ

=O

end;

Tot

Hea

pAR

TV

ec"[

1J:=

1;

for

Arb

inde

x:=O

to

max

v do

be

gin AR

TBTC

" [A

rbin

dexJ

:=

O;

SRT1

BTC

"[A

rbin

dexJ

:=O

; SR

T2B

TC

"[A

rbin

dexJ

:=O

; T

otH

eapC

onv1

"CA

rbin

dexJ

:=O

; T

otH

eapC

onv2

"[A

rbin

dexJ

:=O

; en

end;

'

{***

Impo

sed

BC

for

heap

. }

2

n Q

Q.. ~

~ -· .tll ~ s· Q' .., :: Q

Q.. ~

,;\ n ~ ~ 0

0 .

Page 180: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

1/19

95

08:2

7 Fi

lena

me:

M

OO

EL6C

1.PA

S Pa

ge

3

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re G

ener

ate_

Uni

tHea

pDat

aFil

es;

{Thi

s pr

oced

ure

is u

sed

to g

ener

ate

the

Uni

tHea

pDat

aFil

es.

The

file

s are

}

{nam

ed M

6C1H

1 th

roug

h to

M6C

1HX.

)

var U

nitH

eapN

oS,F

ileN

ame

Hea

pFil

e

begi

n for

Uni

tHea

plnd

ex:=

1 to

NoU

nitH

eaps

do

be

gin Str

(Uni

tHea

plnd

ex,U

nitH

eapN

oS);

Fi

leN

ame:

=Con

catC

'M6C

1H',U

nitH

eapN

oS,'

.Oat

');

assi

gn(H

eapF

ile,

Fil

eNam

e);

rew

rite

(Hea

pFil

e);

for

Siz

elnd

ex:=

1 to

M do

be

gin fo

r A

rbln

dex:

=O

to N

+1

do

begi

n

:Str

ing

; :T

ext;

wri

te(H

eapF

ile,

AR

T"[

Siz

elnd

ex,A

rb!n

dexJ

,' ')

; w

rite

(Hea

pFil

e,S

RT

1"[S

ize!

ndex

,Arb

!nde

xl, •

')

; w

rite

lnC

Hea

pFil

e,S

RT

2"C

Siz

e!nd

ex,A

rbln

dexJ

>;

end·

w

rite

lnC

Hea

pFil

e);

end;

',Uni

tHea

pCon

v2);

w

rite

lnC

Hea

pFil

e,U

nitH

eapC

onv1

, •

wri

teln

(Hea

pFil

e);

wri

teln

(Hea

pFil

e,'C

umT

ime

1,C

umT

ime)

; cl

ose(

Hea

pFil

e);

end·

en

d;

'

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re R

ead_

AR

T_an

d_SR

Ts;

var U

nitH

eapN

oS,F

ileN

ame

Hea

pFil

e

begi

n Str

(Uni

tHea

plnd

ex,U

nitH

eapN

oS);

Fi

leN

ame:

=Con

cat(

'M6C

1H',U

nitH

eapN

oS, '.

Oat'

);

assi

gn(H

eapF

ile,

Fil

eNam

e);

rese

tCH

eapF

ile)

; fo

r S

izel

ndex

:=1

to M

do

begi

n for

Arb

lnde

x:=O

to

N d

o be

gin read

(Hea

pFil

e,A

RT

"[S

izel

ndex

,Arb

Jnde

xl )

; re

ad(H

eapF

ile,

SR

T1"

[Siz

elnd

ex,A

rbln

dexl

);

read

ln(H

eapF

ile,

SR

T2"

CS

izeJ

ndex

,Arb

lnde

xl);

en

read

(Hea

pFil

e,A

rbV

alue

);

AR

T"[

Size

lnde

x,N

+1l

:=T

otH

eapA

RT

Vec

"[U

nitH

eapl

ndex

l; re

ad(H

eapf

ile

SRT

1"[S

izel

ndex

,N+1

J >;

re

adln

CH

eapF

i(e,

SR

T2"

[Siz

elnd

ex,N

+1J

);

:Str

ing

; :T

ext;

07/3

1/19

95

08:2

7 F

ilen

ame:

M

OO

EL6C

1.PA

S Pa

ge

4

end·

re

adln

(Hea

pFil

e,H

oldC

onv1

,Hol

dCon

v2);

cl

ose(

Hea

pFi

le);

end;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--)

Pro

cedu

re Y

rite_

AR

T_a

nd_S

RT

s;

var U

nitH

eapN

oS,F

ileN

ame

Hea

pF i

le

begi

n Str

(Uni

tHea

plnd

ex,U

nitH

eapN

oS);

F

ileN

ame:

=C

onca

t(1M

6C1H

1,U

nitH

eapN

oS,

1.0

at1);

assi

gn(H

eapF

ile,

Fil

eNam

e);

rew

rite

(Hea

pF

ile)

; fo

r S

ize!

ndex

:=1

to M

do

begi

n for

Arb

lnde

x:=O

to

N+1

do

be

gin if A

RT-

CS

izel

ndex

,Arb

inde

xl>

FC

onc

Tol

th

en

wri

te(H

eapF

ile,

AR

T"[

Siz

elnd

ex,A

rbJn

dexl

,' el

se wri

te(H

eapF

ile,

0.00

0,0

');

if S

RT

1"[S

izel

ndex

,Arb

lnde

xJ>

SC

onc_

Tol

th

en

wri

te(H

eapF

ile,

SR

T1"

[Siz

elnd

ex,A

rbln

dexJ

,' el

se wri

te(H

eapF

i le

,0.0

00

, •

• );

if S

RT

2"[S

izel

ndex

,Arb

lnde

x]>

SC

onc_

Tol

th

en

wri

teln

(Hea

pFil

e,S

RT

2"[S

izel

ndex

,Arb

lnde

xl)

else

wri

teln

(Hea

pF

ile,

0.0

00

);

I )

:Str

ing

; :T

ext;

I )

end;

w

rite

ln(H

eap

Fil

e);

end·

w

rite

ln(H

eapF

ile,

Uni

tHea

pCon

v1,

• ',U

nitH

eapC

onv2

);

wri

teln

(Hea

pF

ile)

; w

rite

ln(H

eapF

ile,

•cum

Tim

e 1,C

umtim

e);

clos

e(H

eapF

i le

);

Uni

tHea

pCon

v1:=

0;

Uni

tHea

pCon

v2:=

0;

end;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re O

eter

min

e_M

axim

um_O

elta

T_f

n_Si

ze;

begi

n for

Uni

tHea

plnd

ex:=

1 to

NoU

nitH

eaps

do

be

gin fo

r S

izel

ndex

:=1

to M

do

end;

OT

for

Yat

chS

ize"

[Uni

tHea

plnd

ex,S

izel

ndex

J :=

Max

Oel

taT

-

*S

ize0

ata[

Siz

eln

dex

,1l*

Siz

e0at

a[S

izel

nd

ex,1

J /S

ize0

ata[

M,1

J/S

ize0

ata[

M,1

l;

for

Uni

tHea

plnd

ex:=

1 to

NoU

nitH

eaps

do

Y

atch

Siz

eOT

[Uni

tHea

plnd

exl:

=M

;

end;

Page 181: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

1/19

95

08:2

7 Fi

lena

me:

M

ODEL

6C1.P

AS

Page

5

(-·-

----

----

----

----

--·-

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re D

eter

min

e_C

orre

spon

ding

_Col

Oel

taT

;

(Thi

s pr

oced

ure

uses

th

e m

etho

d of

ch

arac

teri

stic

s to

det

erm

ine

the

} {p

rogr

essi

on i

n tim

e fo

r a

give

n C

harC

olO

elta

E.

It a

llow

s fo

r un

stea

dy

} {

stat

e fl

ow.

}

begi

n Intl

eng

th

:=O

; C

olD

elta

t:=

O;

whi

le

IntL

engt

h<>

lntL

engt

hCri

t do

be

gin

if E

OF(

SupV

elFi

le)

then

beg

in

clos

eseg

raph

ics;

w

rite

ln('

Insu

ffic

ien

t D

ata

in t

he S

up

erfi

cial

Vel

ocit

y D

ata

Fil

e to

');

wri

teln

('ex

ecu

te t

he r

equi

red

num

ber

of

itera

tio

ns.

');

wri

teln

('P

rese

nt

num

ber

of

iter

atio

ns:

=

1,T

imeC

ount

er);

C

ontin

ue:=

IntL

engt

h:=

intL

engt

hCri

t;

read

ln;

end·

In

tlen

gth:

=ln

tLen

gth+

(Sup

Vel

Dat

a[2,

1]-S

upV

elD

ata[

1, 1

J)*S

upV

elD

ata[

2,2J

; C

olD

elta

t:=

Col

Del

ta_t

+(S

upV

elD

ata[

2,1]

-Sup

Vel

Dat

a[1,

1])

; If

In

tlen

gth>

lntL

engt

hCri

t th

en b

egin

A

rbV

alue

:=In

tlen

gth-

Intl

engt

hCri

t;

Col

Del

ta t

:=C

olD

elta

t-

Arb

Val

ue/S

upV

elD

ata[

2,2J

; In

tLen

gtfi

:=In

tLen

gthC

rit;

S

upV

elD

ata[

1,1J

:=S

upV

elD

ata[

2,1J

-Arb

Val

ue/S

upV

elD

ata[

2,2J

; su

pVel

Dat

a[1,

2J:=

Sup

Vel

Dat

a[2,

2J;

end

else

beg

in

SupV

eLD

ata[

1, 1

1:=

Sup

Vel

Dat

a[2,

1J;

SupV

elD

ata[

1,2]

:=

Sup

Vel

Dat

a[2,

2J;

read

(Sup

Vel

Fi l

e,

SupV

elD

ata

[2.,

1]

);

read

(Sup

Vel

Fil

e,

Sup

Vel

Dat

a[2,

2])

end·

en

' C

olD

elta

T:=

Col

Del

ta t

*uS

tar/

Col

Len

gth;

C

umTi

me:

=Cum

Tim

e+C

oTD

elta

T;

end;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re D

eter

min

e_A

ppro

pria

te_R

ef_S

ize_

Cla

ss_D

elta

T;

begi

n Siz

eind

ex:=

Wat

chS

izeD

T[U

nitH

eapl

ndex

];

Iter

atio

ns:=

INT

(CoL

Del

taT

/CD

T

for

Wat

chS

ize"

[Uni

tHea

plnd

ex,S

izei

ndex

J))

+1 ·

--

Del

taT

:=C

olD

elta

T/I

tera

tion

s;

wri

teln

(Siz

eind

ex);

en

d;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re C

heck

_Whe

ther

_Wat

chS

ize_

Sti

ll_V

alid

;

var F

lag

Inte

rG1

Inte

gVal

Inte

ger;

V

eryL

ongV

ecto

r;

Rea

l;

07/3

1/19

95

08:2

7 F

ilen

ame:

M

OD

EL6C

1.PA

S Pa

ge

6

begi

n Siz

eind

ex:=

Wat

chS

izeD

T[U

nitH

eapi

ndex

];

Flag

:=O

; if

AR

T"[

Siz

eind

ex,N

]<0.

5*A

RT

"[S

izei

ndex

,(N

+1)

] be

gin fo

r A

rbin

dex:

=O

to N

do

then

begi

n . i

f (A

RT

"[S

izei

ndex

,Arb

inde

xJ<

0.8*

AR

T"[

Siz

eind

ex,C

Arb

inde

x+1)

l)

or

(ART

0

[Siz

elnd

ex,A

rbin

dex]

>1.

2*A

RT

"[S

izei

ndex

,(A

rbin

dex+

1)])

th

en F

lag:

=F

lag+

1;

end·

~d•

I

if F

lag=

O

then

be

gin fo

r A

rbln

dex:

=O

to N

+1

do

Inte

rG1

[Arb

inde

xJ:=

AR

T"[

Siz

eind

ex,A

rbln

dexJ

; In

tegr

ateV

ecto

r(In

terG

1,D

elta

E,0

,(N

+1)

,lnt

egV

al);

fo

r A

rbln

dex:

=O

to N

+1

do

if

(AR

T"[

Siz

elnd

ex,A

rbin

dex]

<(0

.9*I

nteg

val)

) or

(A

RT

"[S

izei

ndex

,Arb

inde

xl>

(1.1

*1nt

egva

l))

then

Fla

g:=

1;

if

(Fla

g=O

) an

d (W

atch

Size

DT

[Uni

tHea

pind

exl>

1)

then

W

atch

Size

DT

[Uni

tHea

pind

exJ:

=W

atch

Size

DT

[Uni

tHea

pind

exJ-

1;

end

else

if

AR

T"(

Size

inde

x,N

t1l>

FCon

c_T

ol

then

DT

_for

_Wat

chSi

ze"[

Uni

tHea

plnd

ex

,Siz

eind

exl

:=2*

DT

_for

_Wat

chS

ize"

[Uni

tHea

plnd

ex,S

izei

ndex

l;

·

end;

(---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re U

pDat

e_T

otH

eapC

onv;

begi

n Tot

Hea

pCon

v1"[

Col

lter

sJ:=

Tot

Hea

pCon

v1"(

Col

iter

sJ

+Glo

bWet

Fac*

Uni

tKea

pCon

v1/N

oUni

tHea

ps;

Tot

Hea

pCon

v2·c

coli

ters

] :=

Tot

Hea

pCon

vz·c

coll

ters

] +G

lobW

etFa

c*U

nitH

eapC

onv2

/NoU

nitH

eaps

; en

d;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re U

pDat

e_T

otH

eapV

ecto

r;

begi

n Tot

Hea

pAR

TV

ec"[

Uni

tHea

plnd

ex]

:=A

RT

"C1,

N+1

l; T

otH

eapS

olSR

T1V

ec"[

Uni

tHea

plnd

exl:=

Tot

Hea

pSol

SRT

1Vec

"[U

nitH

eapi

ndex

J+

(Uni

tHea

pcon

v1-H

oldC

onv1

);

Tot

Hea

pSol

SRT

2Vec

"[U

nitH

eapi

ndex

l:=T

otH

eapS

olSR

T2V

ec"[

Uni

tHea

plnd

ex]+

(U

nitH

eapC

onv2

-Hol

dCon

v2);

en

d;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re

Incr

emen

t_T

otH

eapV

ecto

rs_a

nd_B

TC

Vec

tors

;

begi

n AR

TB

TC

"[C

olite

rs +

1]

:=T

otH

eapA

RT

Vec

"[N

oUni

tHea

psl;

SRT

1BT

C"[

Col

lters

+1J

:=G

lobW

etFa

c*(T

otH

eapS

olSR

T1V

ec·[

NoU

nitH

eaps

J);

SRT

2BT

C"[

Col

iters

+1J

:=G

lobW

etFa

c*(T

otH

eapS

olSR

T2V

ec"[

NoU

nitH

eaps

]);

for

Arb

lnde

x:=N

oUni

tHea

ps d

ownt

o 2

do

begi

n Tot

Hea

pArt

Vec

"[A

rbin

dexJ

:=

Tot

Hea

pArt

Vec

"[A

rbln

dex-

11;

Tot

Hea

pSol

SRT

1Vec

"[A

rbln

dexJ

:=T

otH

eapS

olSR

T1V

ec"[

Arb

lnde

x-1J

;

Page 182: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

1/19

95

08:2

7 Fi

lena

me:

M

ODEL

6C1.P

AS

Page

7

Tot

Hea

pSol

SRT

2Vec

·[Arb

lnde

x] :

=T

otH

eapS

olSR

T2V

ec·[

Arb

lnde

x-1J

; en

Tot

Hea

pArt

Vec

"[1]

:=1;

T

otH

eapS

olSR

T1V

ec"[

1]:=

0;

Tot

Hea

pSol

SRT

2Vec

·[1]

:=O

;

end;

{---

----

----

----

----

----

----

----

--·-

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re G

raph

_Con

vers

ion_

and_

BT

C_C

urve

s;

begi

n init

SE

Gra

phic

s(V

alid

Dir

);

SetC

urre

ntW

indo

w(2

);

Bor

derC

urre

ntW

indo

w(1

);

Set

Axe

sTyp

e(0,

0);

Sca

leP

lotA

rea(

0.0,

0.0,

(Tim

eVec

tor·

[col

lter

sl),

GfM

ax Y

); (*

**}

Set

XY

lnte

rcep

ts(0

.0,0

.0);

-

Set

Col

or(2

);

Dra

wX

Axi

s((T

imeV

ecto

r·cc

ollt

ersJ

/5),

1);

(*

**}

Dra

wY

Axi

s((G

fMax

Y

/5),

1);

L

abel

XA

xisC

1,0)

;-L

abel

YA

xis(

1,0)

; T

itle

XA

xis(

'Dm

lss

Tim

e (D

mls

s T

ime=

(tim

e *

uS

tar)

/Co

llen

gth

');

Tit

leY

Axi

s('F

rac.

C

onv.

an

d BT

C C

urve

s');

T

itleW

indo

wC

'Mod

el6C

1');

L

abel

Gra

phW

indo

w(1

,930

,GL

abel

1,0,

0);

Lab

elG

raph

Win

dow

(1,9

00,G

labe

l2,0

,0);

fo

r A

rbln

dex:

=O

to C

oll

ters

do

Dat

aSet

X"[

Arb

lnde

xJ

=T

imeV

ecto

r-[A

rbln

dexJ

; fo

r A

rbln

dex:

=O

to C

oll

ters

do

Dat

aSet

Y"[

Arb

lnde

xJ

=Tot

Hea

pCon

v1"[

Arb

lnde

xJ;

Lin

ePlo

tDat

a(D

ataS

etx·

,oat

aSet

Y·,

ccol

lter

s +

1),

5,0

) fo

r A

rbln

dex:

=O

to C

oll

ters

do

Dat

aSet

Y"[

Arb

lnde

x]

=Tot

Hea

pCon

v2"[

Arb

lnde

xJ;

Lin

ePlo

tDat

a(D

ataS

etx·

,Dat

aSet

Y",

(Col

lter

s +

1),

4,0

) fo

r A

rbln

dex:

=O

to C

oll

ters

do

Dat

aSet

Y-[

Arb

lnde

xJ

=AR

TB

TC

-[A

rbln

dexl

; L

ineP

lotD

ata(

Dat

aSet

x· ,D

ataS

etY

",(C

ollt

ers

+1)

,3, 1

) fo

r A

rbln

dex:

=O

to C

oll

ters

do

Dat

aSet

v· [

Arb

lnde

xl

=SR

T1B

TC

"[A

rbln

dexJ

; L

ineP

lotD

ata(

Dat

aSet

x",D

ataS

etv·

,cco

llte

rs +

1),

5,1

) fo

r A

rbln

dex:

=O

to C

oll

ters

do

Dat

aSet

Y"[

Arb

lnde

x]

=SR

T2B

TC

"[A

rbln

dexJ

; L

ineP

lotD

ata(

Dat

aSet

x",D

ataS

etY

",(C

ollt

ers

+1

),4

,1)

end;

(===

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

==}

{MAI

N PR

OGRA

M:

} {=

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

} be

gin ne

w(B

eta1

_k);

ne

w(K

appa

P1_k

); ne

w(K

appa

S1_k

); ne

w(L

ambd

a1

k);

new

(Con

tRat

loV

1);

new

( AR

T);

new

(SR

T1)

; ne

w(S

RT

2);

new

(Bet

a2

k);

new

(Kap

paP2

_k);

new

(Kap

paS2

_k);

new

( Lam

bda2

k)

; ne

w(C

ontR

atlo

V2>

; ne

wC

AR

TP1)

; ne

w(S

RT

1P1)

; ne

w(S

RT

2P1)

;

new

(Del

taT

_k);

new

(SR

T1P1

C);

new

(SR

T2P1

C);

07/3

1/19

95

08:2

7 F

ilen

ame:

M

ODEL

6C1

.PA

S Pa

ge

8

new

(Dat

aSet

X);

ne

w(A

Mat

rix)

; ne

w(A

RTB

TC);

new

(Tot

Hea

pAR

TV

ec);

new

(Tot

Hea

pCon

v1);

ne

w(D

T_f

or_W

atch

Size

);

new

(Dat

aSet

Y);

ne

w(A

lnve

rse)

; ne

w(S

RT1

BTC

); ne

w(T

otH

eapS

olSR

T1V

ec);

ne

w(T

otH

eapC

onv2

);

assi

gn(C

onvR

esul

ts,'C

onvR

esul

ts.D

at')

; re

wri

te(C

onvR

esul

ts);

cl

ose(

Con

vRes

ults

);

lnit

iali

se_

Var

iou

s_V

aria

ble

s;

Siz

e D

istr

ibu

tio

n I

nit

iali

sati

on

; C

onta

min

ant

Loc

atio

n In

itia

lisa

tio

n;

Oet

erm

ine_

Mod

el_P

aram

eter

s_fn

_Siz

e;

lnit

iali

se_

Su

per

fici

al_

Vel

oci

ty_

Fil

e;

, C

ol

Init

ial

Con

diti

ons;

P

arti

cle

Init

ial

Con

diti

ons;

G

ener

ate=

Uni

tHea

poat

aFil

es;

Det

erm

ine_

Max

imum

_Del

taT

_fn_

Size

;

whi

le C

ollt

ers<

Spe

cCol

lter

s do

be

gin Co

llte

rs:=

Co

llte

rs+

1;

Det

erm

ine

Cor

resp

ondi

ng C

olD

elta

T;

Tim

eVec

tor·

ccol

lter

sJ:=

Cum

Tim

e;

for

Uni

tHea

plnd

ex:=

1 to

NoU

nitH

eaps

do

begi

n Rea

d AR

T an

d SR

Ts;

if A

RT-

cT,N

+TJ>

FCon

c To

i th

en

begi

n -

Clo

sese

grap

hics

;

new

(SR

T2B

TC);

new

(Tot

Hea

pSol

SRT

2Vec

);

new

(T im

eVec

tor)

;

Det

erm

ine

App

ropr

iate

Ref

S

ize

Cla

ss D

elta

T;

Det

erm

ine-

Del

taT

fn

Siz

e;-

--

Exe

cute

Uni

t6C

1;-

-C

heck

_Wne

ther

_Wat

chS

ize_

Sti

ll_V

alid

; en

upD

ate_

Tot

Hea

pcon

v;

UpD

ate

Tot

Hea

pVec

tor;

W

rite

ART

an

d SR

Ts;

end;

-

--

lncr

emen

t_T

otH

eapV

ecto

rs_a

nd_B

TC

Vec

tors

;

Ass

ign(

Con

vRes

ults

,'Con

vRes

ults

.Dat

');

App

end(

Con

vRes

ults

);

Wri

teln

(Con

vRes

ults

,Tim

eVec

tor-

[Col

lter

sJ:8

:4,'

,Tot

Hea

pCon

v1"[

Col

lter

sJ:8

:4);

C

lose

(Con

vRes

ults

);

end;

Gra

ph_C

onve

rsio

n_an

d_B

TC

_Cur

ves;

read

ln(H

ardC

opy)

;

Page 183: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

~

~

ro ~ ~ II

II II II II II II II II II II

" II II

" ~ " ~ II 0 II ~ " ~ " ~ " 0 " " II

II

0 II

" ~ II ~ II ~ II ~ II

~ II II

u II ~ II ~ N " w " 0 0 " a " ~ " ~ II

~ II ~ II E E II ro ~ II c 0 II ~ c II

~ II ~ II ~ II u II ~ II

II c II ~ II ~ .. II ~ 00 II

~ u II N II

II ~ II ~ ~ ~ ~ a ~ ro " 0 ~ " u ~ " ~ ~ ~ " ~ ~ 00 " ~ ro ~ " ~ 00 " 0 " ~ " ~ u

~ " " ~ c II 0 ~ ~

Page 184: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

06/1

6/19

95

15:5

1 F

ilen

ame:

U

NIT

6C1.

PAS

Page

1

Uni

t U

ni t.

6C1;

{Uni

t6C

1.

{ *

Th

is p

rogr

am

is s

imil

ar t

o

* Th

e pr

ogra

m c

alcu

late

s th

e an

d so

lid

rea

ctan

ts w

ithi

n de

velo

ped

by D

ixon

.

Mod

el5E

1.PA

S.

} co

nce

ntr

atio

n p

rofi

le o

f fl

uid

}

{ { { { { { { { {

* T

his

prog

ram

onl

y pr

ovid

es a

par

ticl

e us

ing

the

equa

tion

s as

} }

for

soli

d r

eact

ant

ord

ers

of

1.

}

* A

ssum

ptio

ns

in t

his

mod

el

incl

ude:

}

-Th

e so

lid

rea

ctan

t d

epo

sits

wit

hin

the

part

icle

}

rese

mbl

e th

ose

on

the

surf

ace.

}

-Th

e d

epo

sits

wou

ld

both

re

act

to t

he

sam

e ex

ten

t }

if e

ach

wer

e ex

pose

d to

the

sam

e ac

id c

on

cen

trat

ion

}

for

the

sam

e ti

me.

}

{Cod

ed:

Gra

ham

Dav

ies.

}

{ D

epar

tmen

t of

C

hem

ical

E

ngin

eeri

ng.

} {

Uni

vers

ity

of

Cap

e To

wn.

}

{ 28

F

ebru

ary

1995

. }

{ 06

Ju

ne

1995

U

pdat

ed

(GM

O).

} {=

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

} In

terf

ace

{===

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

==}

{Dec

lara

tio

ns:

}

uses

crt

,std

hd

r,g

j,g

rap

h,w

orl

dd

r,se

gra

ph

,in

teg

rat,

M2

C1

Bre

ntR

oo

ts;

cons

t

{***

The

se a

re t

he p

aram

eter

s ap

pli

cab

le t

o t

he r

efer

ence

siz

e cl

ass.

**

*}

Bet

a1

Kap

paP1

0.

264;

4

.5;

Bet

a2

= 0

.0;

Kap

paP2

=

0.0

;

Voi

dage

0.

01;

M

=1

Ref

Siz

eCl

=5;

' V

iew

Size

Cl=

5;

{Dim

ensi

onle

ss S

toic

hiom

etri

c ra

tio

def

ined

pg

11

} {R

atio

of

reat

ion

rat

e of

so

lid

rea

ctan

t re

sid

ing

}

{wit

hin

the

par

ticl

e to

por

ous

dif

fusi

on

of

flu

id

} {

into

th

e p

art

icle

. D

efin

ed p

g 11

D

ixon

. }

{Voi

dage

of

the

soli

d p

arti

lces

.(P

oro

sity

) }

{Num

ber

of s

ize

clas

ses.

}

{Def

ines

the

ref

eren

ce s

ize

clas

s.

} {T

he

con

cen

trat

ion

P.r

ofil

es o

f th

is s

izec

lass

are

}

{gra

phed

in

gra

ph

1:

(NB

Vie

wSi

zeC

l <=

M

.) }

{***

The

se a

re n

umer

ical

m

etho

d pa

ram

eter

s.**

****

****

****

****

****

****

***}

N

=19;

Del

taE

=

1/(N

+1)

;

Max

Del

taT

=

0.00

1;

Nor

m C

rit

=le

-6·

-,

{Hal

f th

e nu

mbe

r of

in

teri

or

po

ints

. r=

O

and

r=R

} {n

ot

incl

uded

. }

{Spa

ce

Incr

emen

t.

Cal

cula

ted

from

1/

CN

+l)

. (S

ince

}

{ R

=i*d

E an

d R

is

at p

oint

N+1

.) }

{Max

imum

per

mit

ted

tim

e in

crem

ent

for

part

icle

s.

}

{Con

verg

ence

cri

teri

a b

ased

on

the

norm

of

vec

tor

} {*

**

}

06/1

6/19

95

15 :5

1 F

ilen

ame:

U

NIT

6C1.

PAS

Page

Con

v C

rit

=1e

-8

SCon

c To

l =1

e-4

FC

on

()o

l =1

e-4

Max

lter

=1

00;

Pri

nt_

Cri

t=1

;

{Con

verg

ence

cri

teri

a f

or

the

Bre

nt R

outi

ne.

} {D

imen

sion

less

co

nce

ntr

atio

n o

f so

lid

bel

ow w

hich

}

{Dim

ensi

onle

ss c

on

cen

trat

ion

of

flu

id

reac

tan

t }

{bel

ow w

hich

it

is

ass

umed

to

be

neg

igib

le.

} {

it

is a

ssum

ed

to b

e n

egli

gib

le.

} {M

axim

um

itera

tio

ns

for

the

Bre

nt R

outi

ne.

}

{***

Oth

er

info

rmat

ion

requ

ired

.***

****

****

****

****

****

****

****

****

****

*}

Val

idD

ir

='F

:\T

P6

\';{

Val

id d

irec

tory

fo

r g

rap

hic

s d

riv

ers.

}

Ord

SP1

Ord

SP2

=1.

0;

=1.

0;

{Rea

ctio

n or

der

of

the

soli

d

in t

he

po

res.

{F

or

this

pro

gram

th

ese

need

to

be

set

at u

nit

y.

{See

Uni

t6C

2 fo

r v

aria

ble

ord

er

reac

tio

n o

rder

s.

} } }

{***

****

****

****

****

****

****

****

****

****

****

****

****

****

****

****

****

***}

type

var ar

ray

l= A

rray

[1 .

. 50,

1 ..

2J

of D

oubl

e;

Tot

Vol

Par

t,V

olL

iq,D

elta

T,I

tera

tion

s,C

umT

ime

Uni

tHea

pCon

v1,U

nitH

eapC

onv2

A

rbin

dex,

Siz

elnd

ex,e

rror

,Uni

tHea

pind

ex

Rep

eats

,Plo

t_V

ar,F

lag1

,Har

dCop

y D

ataS

etX

,Dat

aSet

Y

.

:Dou

ble;

:D

oubl

e;

: In

teg

er;

Bet

a1_k

,Bet

a2 k,KappaP1_k,K~ppaP2_k,KappaS1_k,KappaS2_k

Lam

bda1

k,

Lam

£ida

2_k,

Con

tRat

10V

1,C

ontR

atio

V2

Del

taT

K

AR

T,A

RTP

1,SR

T1,S

RT2

,SR

T1P1

,SR

T2P1

,SR

T1P1

C,S

RT2

P1C

A

Mat

rix,

Ain

vers

e

: In

teg

er;

:·ve

ryL

ongV

ecto

r;

: "S

hort

Vec

tor;

: ·

sho

rtV

ecto

r;

AR

TP1

CV

al,S

umSi

zeD

ata

2,N

uSta

r L

ambd

a1,L

ambd

a2,K

appa

S1,K

appa

S2

GL

abel

1,G

labe

l2,G

Lab

el3

Siz

eDat

a :

Arr

ay[1

.•

50, 1

•• 2

] of

Rea

l;

{ART

A

lpha

fn

(r)

at

tim

e T

{A

RTP1

A

lpha

fn

(r)

at

tim

e T+

1 {S

RT1

Sigm

a fn

(r)

at

tim

e T

{S

RTs

P1

Sigm

a fn

(r)

at

tim

e T+

1 (g

uess

ed)

: "A

rray

1;

:"S

qrM

at;

:·sq

rMat

; :E

xten

ded;

:E

xten

ded;

:S

trin

g;

rang

e o· •

. M

0 •. N

+1}

rang

e O

.• M

0

.• N

+1}

rang

e 0

•. M

0 ..

N+1

} ra

nge

O •.

M

0 •. N

+1}

{SR

TsP1

C

Sigm

a fn

(r)

at

tim

e T+

1 (c

alcu

late

d)

rang

e O

•• M

0

•. N

+1}

{YV

ect

'Co

nst

' v

ecto

r in

Crank~Nicolson

met

hod

rang

e O

•. N

+1

} C

AM

atrix

M

atri

x of

Cra

nk-N

icol

son

coef

fici

ents

ra

nge

N*

N

} {D

ataS

etX

X

vec

tor

used

in

the

gra

phin

g ro

uti

ne

rang

e 0

.• N

+1

}

{***

****

****

****

****

****

****

****

****

****

****

****

****

****

****

****

****

***}

Pro

cedu

re S

ize

Dis

trib

uti

on

In

itia

lisa

tio

n;

Pro

cedu

re C

onta

min

ant

Loc

atT

on

Init

iali

sati

on

; P

roce

dure

Det

erm

ine

Mod

el

Par

amet

ers

fn S

ize;

P

roce

dure

Det

erm

ine-

Del

taT

fn

Siz

e; -

-P

roce

dure

Par

ticl

e_T

nit

ial=

Co

nd

itio

ns;

P

roce

dure

Gue

ss

SRTs

P1;

Pro

cedu

re R

eGue

ss

SRTs

P1;

Pro

cedu

re C

ale

Cra

nk

Nic

olso

n M

atri

x(va

r Y

Vec

tor

:Sh

ort

Vec

tor)

; P

roce

dure

Cal

c=A

RTP

1=an

d_SR

TsP1

C;

2

Page 185: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

"

06/1

6/19

95

15:5

1 Fi

lena

me:

U

NIT

6C1.

PAS

Page

3

Pro

cedu

re C

heck

Con

verg

ence

; P

roce

dure

Upd

ate_

AR

T_an

d_SR

Ts;.

Pro

cedu

re C

ale

Con

vers

ion;

P

roce

dure

Gra

pn1_

Init

iali

se;

Pro

cedu

re G

raph

1 R

esul

ts;

Pro

cedu

re E

xecu

te_U

nit6

C1;

f ~~1;

~;~~

~~i~

~===

====

====

====

====

====

====

====

====

====

====

====

====

====

====

=}

{===

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

==}

Pro

cedu

re S

i ze_

Di s

trib

uti

on_!

ni. ti

al i

sat

ion;

{Thi

s pr

oced

ure

sets

up

the

size

dis

trib

uti

on

dat

a ar

ray

. In

itia

lly

the

}

{Siz

eDat

a ar

ray

con

tain

s ra

dius

in

form

atio

n an

d fr

acti

on

al

volu

me

} {i

nfor

mat

ion

(ie

R a

nd V

p/V

tot)

. On

out

put

it c

onta

ins

rela

tiv

e ra

dius

}

{inf

orm

atio

n an

d re

lati

ve

volu

me

info

rmat

ion

Cie

R/

R re

f an

d V

p/V

p re

f).

} {

Idea

lly

th

is

info

rmat

ion

wou

ld.b

e re

ad

in f

rom

a

data

fil

e.

-}

var R

efR

adiu

s,V

olR

efP

art

:Dou

ble;

begi

n Size

Dat

aC.1

, 11

= 3

7.00

e-3/

2 s

zeD

ata

[1, 2

1 =

58.

1/1

00

s i z

eDat

a [2

, 11

= 3

1.25

e-3/

2 S

zeD

ata[

2,21

=

15.

8/10

0 Si

zeD

ataC

3, 1

1 =

22.

00e-

3/2

S ze

Dat

a[3,

21

= 1

0.3/

100

Si z

eDat

a [4

, 11

= 1

6.10

e-3/

2 S

zeD

ata[

4,2l

=

4.

1/10

0 Si

zeD

ata

[5, 1

1 =

11.

35e-

3/2

S ze

Dat

a [5

, 21

=

3.2/

100

Siz

eDat

a[6,

11

=

8.10

e-3/

2 s

zeD

ata

[6, 2

1 =

1.

8/10

0 S

izeD

ata[

7, 11

=

5.

73e-

3/2

S ze

Dat

a[7,

2l

=

1.3/

100

Siz

eDat

a[8,

11

=

4.05

e-3/

2 S

zeD

ata

[8, 2

1 =

1.

0/10

0 S

izeD

ata[

9, 11

=

2.

86e-

3/2

S ze

Dat

a[9,

21

=

0.6/

100

Siz

eDat

aC10

,1l

=

1.18

e-3/

2 S

zeD

ata[

10,2

l =

3.

8/10

0

Vol

Ref

Par

t:=

Tot

Vol

Par

t*S

izeD

ata[

Ref

Siz

eCl,

21;

Ref

Rad

ius

:=S

izeD

ata[

Ref

Siz

eCl,

11;

Sum

Size

Dat

a_2:

=0;

for

Siz

elnd

ex:=

1 to

M do

be

gin Siz

eDat

a[S

izel

ndex

, 11:

=S

izeD

ata[

Siz

elnd

ex,1

1/R

efR

adiu

s;

Siz

eDat

a[S

izel

ndex

,2J:

=S

izeD

ataC

Siz

elnd

ex,2

J*T

otV

olP

art/

Vol

Ref

Par

t;

Sum

Size

Dat

a 2:

=Sum

Size

Dat

a 2+

Siz

eDat

a[S

izel

ndex

,2l;

en

d;

--

NuS

tar:

=V

olL

iq/(

Voi

dage

*Vol

Ref

Par

t);

{Rat

io o

f vo

lum

e of

bu

lk

flu

id t

o fl

uid

in

par

ticl

e po

res.

end;

}

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re C

onta

min

ant_

Loc

atio

n_ln

itia

lisa

tion

;

{Thi

s pr

oced

ure

is u

sed

to d

efin

e th

e co

ntam

inan

t ra

tio

vec

tor

(rati

o o

f }

{th

e su

rfac

e co

ntam

inan

t co

ncen

trat

ion

to b

ulk

cont

amin

ant

con

cen

trat

ion

).}

{NO

TE:

If a

ny s

ize

clas

s of

p

arti

cles

hav

e a

surf

ace

conc

entr

atio

n of

}

{ co

ntam

inan

t,

then

so

too

mus

t th

e re

fere

nce

size

cla

ss.

}

06/1

6/19

95

15:5

1 F

ilen

ame:

U

NJT

6C1.

PAS

Page

4

begi

n Con

tRat

oV

1"[1

l =

0.00

C

ontR

at

oV1"

C21

=0.

00

Con

tRat

oV

1"[3

1 =

0.00

C

ontR

at

oV1"

C4l

=0

.00

Con

tRat

oV

1"[5

] =

0.00

C

ontR

at

oV1"

[6]

=0.

00

Con

tRat

oV

1"[7

] =

0.00

C

ontR

at

oV1"

[8]

=0.

00

Con

tRat

oV

1"[9

] =

0.00

C

ontR

at

ov1·

c101

=

0.00

en

d;

Con

tRat

ov

2"[1

J =O

C

ontR

at

ov2"

[2J

=O

Con

tRat

ov2

"[3]

=O

C

ontR

at

ov2"

[4l

=O

Con

tRat

ov

2"[5

] =O

C

ontR

at

ov2"

[6J

=O

Con

tRat

ov

2"[7

J =O

C

ontR

at

ov2"

[8J

=O

Con

tRat

ov

2"[9

J =O

C

ontR

at

ov2"

C10

J =O

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re D

eter

min

e_M

odel

_Par

amet

ers_

fn_S

ize;

{Thi

s pr

oced

ure

dete

rmin

es

the

mod

el

para

met

ers

each

si

ze c

lass

of

} {

par

ticl

es.

Not

e th

at

the

Del

taT

is

def

ined

sep

arat

ely

in

anot

her

} {p

roce

dure

. ·

}

var F

lag1

,Fla

g2

:In

teg

er;

begi

n F

lag1

:=0;

F

lag2

:=0;

fo

r S

izel

ndex

:=1

to M

do

begi

n Lam

bda1

k"

[Siz

elnd

exl

:=C

ontR

atio

V1"

[Siz

elnd

exl

-/C

1+C

ontR

atio

V1"

[Siz

elnd

exJ)

; La

mbd

a2

k"[S

izel

ndex

] :=

Con

tRat

ioV

2"[S

izel

ndex

] -

/C1+

Con

tRat

ioV

2"C

Siz

elnd

exJ)

; if

Con

tRat

ioV

1"[S

izel

ndex

J<>

O

then

Fla

g1:=

Fla

g1+

1;

if C

ontR

atio

V2"

[Siz

elnd

exJ<

>O

th

en

Fla

g2:=

Fla

g2+

1;

end;

if

CC

CFl

ag1=

1)

and

(Con

tRat

ioV

1"[R

efS

izeC

lJ=

0))

or

CC

Flag

2=1)

an

d (C

ontR

atio

v2"C

Ref

Siz

eClJ

=0)

))

then

beg

in

clo

sese

gra

ph

ics;

w

rite

ln('

Con

tam

inan

t L

ocat

ion

Vio

loat

ion

.');

re

adln

; en

d;

Lam

bda1

:=

Lam

bda1

_k-C

Ref

Size

ClJ

; La

mbd

a2

:=La

mbd

a2

k"[R

efS

izeC

ll;

Kap

paS1

:=

Lam

bda1

wK

appa

P1/C

1-L

ambd

a1);

Kap

paS2

:=

Lam

bda2

*Kap

paP2

/C1-

Lam

bda2

);

for

Siz

elnd

ex:=

1 to

M do

be

gin Bet

a1

k"[S

izel

ndex

] :=

Bet

a1*(

1+C

ontR

atio

V1"

[Ref

Siz

eCl]

) -

/C1+

Con

tRat

ioV

1"[S

izel

ndex

J);

Bet

a2 k

"[S

izel

ndex

J :=

Bet

a2*C

1+C

ontR

atio

V2"

[Ref

Size

CL

J)

-/C

1+C

ontR

atio

V2"

[Siz

eJnd

exJ)

; K

appa

P1_k

"CSi

zeln

dexJ

:=KaepaP1*Siz~Data[Sizelndex,1J

*S1z

eDat

aCS

1zel

ndex

,1J;

K

appa

P2_k

-CSi

zeln

dexl

:=KaepaP2*Siz~Data[Sizelndex,1J

*S1z

eDat

a[S

1zel

ndex

,1J;

{*

****

Not

e:U

nity

pow

er

assu

mpt

ion

invo

lved

in

next

fe

w

line

s***

**

}

Page 186: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

06/1

6/19

95

15:5

1 Fi

lena

me:

U

NIT

6C1.

PAS

Page

5

if C

ontR

atio

V1"

[Siz

elnd

exJ=

O

then

Kap

paS1

k"

[Siz

elnd

exJ

:=O

el

se

Kap

paS1

_k-

[Siz

elnd

exJ:

=K

appa

S1*C

ontR

atT

oV1"

[Siz

elnd

exJ

/Con

tRat

ioV

1"[R

efS

izeC

LJ*

Siz

eDat

a[S

izel

ndex

,1J;

if

Con

tRat

ioV

2"[S

izel

ndex

J=O

th

en K

appa

S2

k"[S

izel

ndex

J:=

O e

lse

Kap

paS2

_k-

CSi

zeln

dexJ

:=K

appa

S2*C

ontR

atT

oV2"

CSi

zeln

dexJ

/C

ontR

atio

V2"

[Ref

Siz

eCL

J*S

izeD

ata[

Siz

elnd

ex, 1

J;

end­

~d·

, {-

-'.-

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

-}

Pro

cedu

re D

eter

min

e_D

elta

T_f

n_S

ize;

begi

n for

Siz

elnd

ex:=

1 to

M do

D

elta

T

k"[S

izel

ndex

,1J

:=D

elta

T/S

izeD

ata[

Siz

elnd

ex,1

J -

/Siz

eDat

a[S

izel

ndex

,1J;

end;

{---

----

----

----

----

----

----

----

---C

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re P

arti

cle_

Init

ial_

Co

nd

itio

ns;

{Thi

s pr

oced

ure

uses

th

e in

itia

l co

ndit

ions

to

set

th

e al

pha

and

sigm

a } }

surf

ace}

{v

ecto

rs.

{Not

e th

at A

RTCN

+1],

AR

TP1[

N+1

J, SR

T1CN

+1J

and

SRT1

P1[N

+1J

are

the

{con

cent

rati

ons

of

the

Liq

uid

and

soli

d r

eact

ants

.

begi

n for

Siz

elnd

ex:=

1 to

M do

be

gin fo

r A

rbln

dex:

=O

to N

do

begi

n ART"

[S

izel

ndex

,Arb

inde

xJ

:=O

S

RT

1"[S

izel

ndex

,Arb

lnde

xl:=

1 SR

T2"

CSi

zeln

dex,

Arb

lnde

xJ :=

1 SR

T1P1

C" [

Siz

elnd

ex,A

rbin

dex]

=O

;. SR

T2P

1C"[

Size

lnde

x,A

rbin

dexJ

=O

; en

AR

Tt[

Size

lnde

x,N

+1J

:=1;

SR

T1"

[Siz

elnd

ex,N

+1J

:=

1;

SRT2

" [S

izel

ndex

,N+

1J :

=1;

SR

T1P

1C"[

Size

lnde

x,A

rbln

dexl

:=O

; SR

T2P

1C"[

Size

lnde

x,A

rbln

dexJ

:=O

; en

d;

end;

}

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re G

uess

_SR

TsP1

;

{Thi

s pr

oced

ure

prov

ides

the

in

itia

l ''g

uess

" fo

r th

e it

erat

ion

. It

us

es

} {t

he p

revi

ous

tim

e in

terv

al's

val

ues

as

the

gues

s.

}

begi

n for

Siz

elnd

ex:=

1 to

M do

be

gin fo

r A

rbln

dex:

=O ·

to C

N+1

) do

be

gin SR

T1P

1·cs

izel

ndex

,Arb

lnde

xJ:=

SR

T1"

CS

izel

ndex

,Arb

Jnde

xJ;

SRT

2P1"

CSi

zeln

dex,

Arb

lnde

xJ :

=S

RT

2"[S

izel

ndex

,Arb

Jnde

xJ;

end;

06/1

6/19

95

15:5

1 F

ilen

ame:

U

NJT

6C1.

PAS

Page

6

AR

TP

1"[S

izel

ndex

,N+

1J:=

AR

T"[

Siz

eind

ex,N

+1J

; en

end;

'

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re R

eGue

ss_S

RT

sP1;

{Thi

s pr

oced

ure

prov

ides

an

upda

ted

"gue

ss"

for

the

next

it

era

tio

n.

It

} {u

ses

the

SRT1

P1C

vec

tor

as t

he

upda

ted

gues

s.

}

begi

n for

Siz

elnd

ex:=

1 to

M do

be

gin fo

r A

rbln

dex:

=O

to (

N+1

) do

be

gin SR

T1P

1"[S

izel

ndex

,Arb

Jnde

xJ :

=S

RT

1P1C

"[S

izel

ndex

,Arb

lnde

xJ;

SR

T2P

1"[S

izel

ndex

,Arb

Jnde

xJ :

=S

RT

2P1c

·csi

zeln

dex,

Arb

inde

xJ;

end·

A

RT

P1"C

Size

lnde

x,N

+1J:

=AR

TP1

CV

al;

end·

en

d;

' {-

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

} P

roce

dure

Cal

c_C

rank

_Nic

olso

n_M

atri

x(va

r Y

Vec

tor

:Sho

rtV

ecto

r);

{***

**N

ote:

Uni

ty p

ower

as

sum

ptio

n in

volv

ed

in

this

pro

cedu

re**

***

}

var R

ows,

Col

s : I

nte

ger

;

begi

n for

Row

s:=O

to

(N

+1)

do

begi

n for

Col

s:=O

to

CN

+1)

do A

Mat

rix"

CR

ows,

Col

sJ:=

O;

end;

AM

atri

x·co

,OJ:

=(-

6-D

elta

E*D

elta

E*S

izeD

ata[

Siz

eJnd

ex, 1

J*S

ize0

ata[

Siz

elnd

ex, 1

J *C

Kap

paP1

k"

[Siz

elnd

exJ*

SR

T1P

1"[S

izel

ndex

,OJ

+Kap

paP2

f"[

Siz

elnd

exJ*

SR

T2P

1"[S

izel

ndex

,0J)

-2*D

elta

E*D

elta

E

*Siz

eDat

a[S

izel

ndex

,1J*

Siz

eDat

a[S

izel

ndex

,1J

/Del

taT

k

"[S

izel

nd

ex,1

J);

AM

atrix

" CO

, 1J

:=6;

-

YV

ecto

rCO

J :=

AR

T"[

Siz

elnd

ex,O

J*C

6+D

elta

E*D

elta

E*S

izeD

ata[

Siz

elnd

ex,1

J *S

izeD

ata[

Siz

elnd

ex,1

J*C

Kap

paP

1_k-

[Siz

elnd

exJ

*SR

T1"

[Siz

eind

ex,O

J+K

appa

P2_

k-[S

izel

ndex

J *S

RT

2"[S

izel

ndex

,0J)

-2*D

elta

E*D

elta

E*S

izeD

ata[

Siz

elnd

ex,1

J *S

izeD

ata[

Siz

elnd

ex,1

]/D

elta

T k

"[S

izel

nd

ex,1

])

-AR

T"[

Siz

elnd

ex,1

J*6;

-

for

Row

s:=1

to N

-1

do

begi

n AM

atri

x"[R

ows,

Row

s-1J

:=R

ows-

1;

AM

atrix

"[R

ows,

Row

sJ

:=-2

*Row

s-R

ows*

Del

taE

*Del

taE

*Siz

eDat

a[S

izel

ndex

,1J

*Siz

eDat

a[S

izel

ndex

,1J*

(Kap

paP

1_k-

CS

izel

ndex

J*

SRT

1P1"

[Siz

elnd

ex,R

owsJ

+Kap

paP2

csiz

elnd

exJ*

SR

T2P

1.[S

izel

ndex

,Row

sJ)-

2*R

owsw

oeL

taE

*D

elta

E*S

izeD

ata[

Siz

elnd

ex,1

J *S

izeD

ataC

Siz

elnd

ex,1

J/D

elta

T_k

·csi

zeln

dex,

1J;

A

Mat

rix·

[R

ows,R

ows+

1] :

=Row

s+1;

Y

Vec

torC

Row

s]

· :=

AR

T"[

Size

lnde

x,R

ows-

1J*C

-Row

s+1)

+ A

RT

.[Siz

elnd

ex,R

owsJ

*C2*

Row

s+R

ows*

Del

taE

*Del

taE

Page 187: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

06/1

6/19

95

15:5

1 Fi

lena

me:

U

NIT

6C1.

PAS

Page

7

*Siz

eDat

a[S

izel

ndex

,1J*

Siz

eDat

a[S

izel

ndex

, 13

*(K

appa

P1

k"[S

izel

ndex

J*S

RT

1"[S

izel

ndex

,Row

sJ

+Kap

paP2

K0

[Siz

e!nd

exJ*

SR

T2"

[Siz

elnd

ex,R

owsJ

) ·2

*Row

s*D

elta

E*D

elta

E*S

izeD

ata[

Siz

elnd

ex, 1

J *S

izeD

ata[

Siz

elnd

ex,1

3/D

elta

T k

"(S

izel

ndex

,1])

+A

RT

"[Si

zeln

dex,

Row

s+1J

*C-R

ows-

1);

end;

AM

atri

x"[N

,N-1

J:=

N-1

; A

Mat

rix"

[N,N

l :=

-2*N

-N*D

elta

E*D

elta

E*S

izeD

ata[

Siz

elnd

ex,1

l *S

izeD

ata[

Siz

elnd

ex,1

J*C

Kap

paP

1 k"

[Siz

elnd

ex]

*SR

T1P

1"[S

izel

ndex

,NJ+

Kap

paP2

k~[Sizelndexl

*SR

T2P

1"[S

izel

ndex

,NJ

)-2*

N*D

eTta

E*D

elta

E

*Siz

eDat

a[S

izel

ndex

,1J*

Siz

eDat

a[S

izel

ndex

, 1]

/Del

taT

k"

[Siz

elnd

ex, 1

3;

YV

ecto

r[N

J :=

AR

T"[

Size

lnde

x,N

-1J*

(-N

+1)+

AR

T"[

Size

lnde

x,N

J*C

2*N

+

end;

N*D

elta

E*D

elta

E*S

izeD

ata[

Siz

elnd

ex, 1

J *S

izeD

ata[

Size

lnde

x,1J

*CK

appa

P1

k"[S

izel

ndex

J *S

RT

1"[S

izel

ndex

,NJ+

Kap

paP2

k"

[Siz

elnd

exJ

*SR

T2"

[Siz

elnd

ex,N

J)-2

*N*D

eTta

E*D

elta

E

*Siz

eDat

a[S

izel

ndex

, 1J*

Siz

eDat

a[S

izel

ndex

, 1J

/Del

taT

k"

[S

izel

ndex

, 1J)

+AR

T"[

Size

lnde

x,N

+1J*

C-N

-1)

-AR

TP1

"[Si

ze!n

dex,

N+1

J*(N

+1);

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re C

alc_

AR

TP1_

and_

SRTs

P1C

;

{As

it s

tand

s th

is p

roce

dure

can

cop

e w

ith a

var

iab

le r

eact

ion

ord

er.

Thi

s}

{is

due

to

the

in

clus

ion

of

the

Bre

nt R

outi

ne.

}

var M

assB

alV

al,A

Mat

Det

V

alue

AtR

oot

· O

utpu

tVec

tor,

YV

ecto

r

begi

n {F

irst

cal

cula

te t

he A

RTP1

v

ecto

rs.

for

Siz

elnd

ex:=

1 to

M do

be

gin

Dou

ble;

R

eal;

S

hort

Vec

tor;

Cal

e C

rank

Nic

olso

n M

atri

x(Y

Vec

tor)

; GaussJordanCAMatrix~,YVector,(N+1),0utputVector,Alnverse·,AMatDet);

for

Arb

lnde

x:=O

to

N d

o

end;

if O

utPu

tVec

tor[

Arb

lnde

xJ>F

Con

c To

i th

en

AR

TP1

"(Si

zeln

dex,

Arb

lnde

xJ :

=O

utpu

tVec

tor[

Arb

lnde

xl

else

·

AR

TP1

"(Si

zeln

dex,

Arb

!nde

xl :

=O;

{The

Gau

ssJo

rdan

pro

cedu

re c

alcu

late

s va

lues

for

th

e AR

T ve

ctor

fr

om

{poi

nt 0

to

poin

t N

(al

thou

gh it

mak

es

use

of

the

N+1

th p

oin

t).

To

{det

erm

ine

the

N+1

th p

oint

val

ue,

mak

e us

e of

th

e m

ass

bala

nce

of

{fl

uid

rea

ctan

t in

-th

e CS

TR.

Mas

sBal

Val

:=O

;

} } } } }

06/1

6/19

95

15:5

1 F

ilen

ame:

U

NIT

6C1.

PAS

Page

8

for

Siz

elnd

ex:=

1 to

M do

be

gin Mas

sBal

Val

:=M

assB

alV

al-S

izeD

ata[

Siz

eind

ex,2

J/2*

CK

appa

S1

k"[S

izel

ndex

l *S

RT

1"[S

ize!

ndex

,CN

+1)

J*A

RT

"[Si

zeln

dex,

CN

+1)

J +

Kap

paS

1_k"

[Siz

elnd

exJ*

SR

T1P

1"[S

izel

ndex

,(N

+1)

J *A

RT

P1"

[Siz

elnd

ex,(

N+

1)J+

Kap

paS

2_k"

[Siz

elnd

exJ

*SR

T2"

[Siz

elnd

ex,C

N+

1)J*

AR

T"[

Siz

elnd

ex,(

N+

1)J

+Kap

paS2

k"

[Siz

elnd

ex]*

SR

T2P

1"[S

izel

ndex

,CN

+1)

J *A

RT

P1"

[Siz

e!nd

ex,(

N+

1)J)

-3*S

izeD

ata[

Siz

elnd

ex,2

J /C

Siz

eDat

a[S

izel

ndex

,1J*

Siz

eDat

a[S

izel

ndex

,1J)

/2

*((A

RT"

(S

ize!

ndex

,(N

+1)

J+A

RT

P1"

[Siz

elnd

ex,(

N+

1)])

-C

AR

T"[

Siz

elnd

ex,N

J+A

RT

P1"

[Siz

elnd

ex,N

J))/

0elt

aE;

end;

AR

TP1

CV

al:=

AR

T"[

1,(N

+1)J

+Del

taT

/NuS

tar*

Mas

sBal

Val

;

{Cal

cula

te t

he S

RTsP

1C

vec

tors

. C

ode

mak

es

use

of

Bre

nt'

s M

etho

d }

{(A

n

on

-lin

ear

root

fi

ndin

g pr

oced

ure)

to

so

lve

for

the

roo

t.

}

for

Siz

elnd

ex:=

1 to

M do

be

gin fo

r A

rbln

dex:

=O

to (

N+1

) do

be

gin

ex, 1

J,

if

(Bet

a1_k

-[S

izel

ndex

J<>

O)

and

(Kap

paP

1_k"

[Siz

elnd

exJ<

>O

) th

en

begi

n if O

rdSP

1=1

then

.

begi

n SR

T1P

1C"[

Siz

elnd

ex,A

rbln

dexJ

:=S

RT

1"[S

izel

ndex

,Arb

lnde

xJ

end

*(1-

Del

taT

k"[

Siz

elnd

ex,1

J*K

appa

P1

k"[S

izel

ndex

] *B

eta1

_k"[

Siz

elnd

exJ*

AR

T"[

Siz

elnd

ex,A

rbln

dex]

/C

2*C

1-La

mbd

a1

k"[S

izel

ndex

])))

/(1+

Del

taT

k"

[Siz

elnd

ex,1

] *K

appa

P1_

k·cs

izel

ndex

J*B

eta1

k

"[S

izel

nd

exr

*AR

TP1

"[Si

zeln

dex,

Arb

!nde

xJ/(

2*C

1-L

ambd

a1

k"[

Siz

eln

dex

])))

.

I -

else

if

SRT

1P1"

[Siz

elnd

ex,A

rbln

dexl

<SC

onc_

Tol

th

en

SR

T1P

1C"[

Siz

elnd

ex,A

rbln

dex]

:=

SR

T1P

1"[S

izel

ndex

,Arb

lnde

xJ

else

be

gin SR

T1P

1C"[

Siz

elnd

ex,A

rbln

dexJ

:=B

rent

Roo

ts(0

.0,1

.0,D

elta

T_k

·csi

zeln

d

Kap

paP1

k"

[Siz

elnd

exJ,

Bet

a1

k"[S

izel

ndex

J,

Lam

bda1

-k"C

Siz

elnd

exJ,

Ord

SP

T,A

RT

"[S

izel

ndex

,Arb

lnde

xJ,

AR

TP

1"[S

izel

ndex

,Arb

lnde

xJ,S

RT

1"[S

izel

ndex

,Arb

lnde

xl,

1e-8

,100

,Val

ueA

tRoo

t,er

ror)

; en

end·

'

if

CB

eta2

_k-[

Siz

elnd

exJ<

>O

) an

d (K

appa

P2_

k"[S

izel

ndex

J<>

0)

then

be

gin ff o

rdSP

2=1

then

be

gin

end S

RT

2P1C

"[S

izel

ndex

,Arb

lnde

xJ:=

SR

T2"

[Siz

elnd

ex,A

rbln

dexJ

*C

1-D

elta

T

k"[S

izel

ndex

,1J*

Kap

paP

2 k"

[Siz

elnd

ex]

*Bet

a2 k

"[S

izel

ndex

l*A

RT

"[S

izel

ndex

,Arb

lnde

xl

/C2*

C17

Lam

bda2

k"

[Siz

elnd

exJ)

))/(

1+D

elta

T k

"[S

izel

ndex

,11

*Kap

paP2

k"

[Siz

elnd

exJ*

Bet

a2_k

"[S

ize!

ndex

r *A

RT

P1"

[Siz

elnd

ex,A

rbin

dexJ

/C2*

C1-

Lam

bda2

_k"[

Siz

elnd

exJ)

))

else

if

SRT

2P1"

[Siz

elnd

ex,A

rb!n

dexl

<SC

onc_

Tol

th

en

Page 188: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

06/1

6/19

95

15:5

1 Fi

lena

me:

U

NIT

6C1.

PAS

Page

9

SR

T1P

1C"[

Siz

elnd

ex,A

rbln

dexJ

:=S

RT

2P1"

[Siz

elnd

ex,A

rbln

dex]

el

se

begi

n SRT2

P1C"

[S

izel

ndex

,Arb

lnde

xJ:=

Bre

ntR

oots

(O.O

, 1.0

, D

elta

T

k"[S

izel

ndex

,1J,

Kap

paP

2 k"

CS

izel

ndex

l,

Bet

a2 f

"[S

izel

ndex

],L

ambd

a2

k"1S

izel

ndex

J,O

rdS

P2,

A

RT

"[S

izel

ndex

,Arb

inde

xJ,A

RiP

1"[S

izel

ndex

,Arb

lnde

xJ,

SR

T2"

CS

izel

ndex

,Arb

lnde

xl, 1

e-8,

100

,Val

ueA

tRoo

t,er

ror)

; en

end·

'

end·

·'

en

' en

d;

'

{---

---·

----

-·--

----

----

······

······

·---

----

----

----

----

----

----

----

----

--}

Pro

cedu

re C

heck

_Con

verg

ence

;

{Thi

s pr

oced

ure

chec

ks w

heth

er

or n

ot

the

solu

tio

n h

as

conv

erge

d by

}

{com

pari

ng

the

gues

sed

valu

e of

SR

T1P1

w

ith

a ca

lcu

late

d v

alue

of

SR

T1P

1.}

<Als

o co

mpa

res

the

calc

ula

ted

val

ue o

f AR

TP1C

w

ith

gues

sed

valu

e of

}

{AR

TP1.

}

var N

orm

1,N

orm

2,N

orm

3

begi

n

:Dou

ble;

Norm

1 =O

; {U

sing

a

norm

***

}

Nor

m2

=O·

· N

orm

3 =O

! fo

r S

zein

dex:

=1

to M

do

begi

n for

Arb

lnde

x:=O

to

(N

+1)

do

begi

n ·

if (

8eta

1 k"

[Siz

elnd

ex]<

>O

) an

d CK

appa

P1

k"[S

izel

ndex

l<>

O)

then

beg

in

Nor

m1:

=Nor

m1+

(SR

T1P

1C"[

Size

lnde

x,A

rbln

dexJ

-S

RT

1P1"

[Siz

elnd

ex,A

rbln

dex]

)*C

SR

T1P

1C"[

Siz

elnd

ex,A

rbln

dex]

-S

RT

1P1"

[Siz

elnd

ex,A

rbln

dexl

);

end

else

Nor

m1:

=0;

. if

(B

eta2

_k"[

Siz

elnd

exJ<

>O

) an

d (K

appa

P2_k

"[Si

zeln

dexJ

<>

0)

then

beg

in

· N

orm

2:=N

orm

2+C

SRT

2P1C

"[Si

zeln

dex,

Arb

lnde

xl

-SR

T2P

1"[S

izel

ndex

,Arb

lnde

xJ)*

(SR

T1P

1C"[

Siz

elnd

ex,A

rbln

dexl

-S

RT

2P1"

[Siz

elnd

ex,A

rbln

dexl

);

end

else

Nor

m2:

=0;

end·

en

' Nor~:=(ARTP1CVal-ARTP1.

C1,N

+1J

)*(A

RTP

1CV

al-A

RTP

1. C

1,N

+1l

);

if (

Nor

m1<

Nor

m C

rit)

and

(N

orm

2<N

orm

Cri

t) a

nd

(Nor

m3<

Nor

m C

rit)

th

en

Fla

g1::

1;

--

end;

{---

----

----

----

----

----

·---

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re U

pdat

e_A

RT_

and_

SRTs

;

{Thi

s pr

oced

ure

upda

tes

the

alph

a an

d si

gma

vect

ors

for

the

next

it

erat

ion

}

{by

repl

acin

g th

eir

com

pone

nts

with

th

e al

phaT

+1

and

sigm

aT+1

v

ecto

rs.

}

begi

n

06/1

6/19

95

15:5

1 F

ilen

ame:

U

NIT

6C1.

PAS

Page

10

for

Siz

elnd

ex:=

1 to

M do

be

gin fo

r A

rbln

dex:

=O

to (

N+1

) do

be

gin AR

T"[

Siz

elnd

ex,A

rbln

dexl

=A

RTP1

" [S

izel

ndex

,Arb

inde

xl;

SR

T1"

[Siz

elnd

ex,A

rbln

dexl

=

SR

T1P

1"[S

izel

ndex

,Arb

lnde

xJ;

SR

T2"

[Siz

elnd

ex,A

rbln

dexl

=

SR

T2P

1"[S

izel

ndex

,Arb

lnde

xJ;

end;

en

end;

'

{---···················-····--·-··---·············-·····-·-·-···-·········}

P

roce

dure

Cal

c_C

onve

rsio

n;

{Thi

s pr

oced

ure

calc

ula

tes

the

frac

tio

nal

co

nver

sion

of

the

par

ticl

e fo

r }

{the

tim

e in

terv

al.

It u

ses

the

form

ula

on

pg.

13

Dix

on.

The

inte

gra

tor}

{

is t

he Q

uinn

-Cur

tis

vec

tor

inte

gra

tor.

}

var ln

terG

1,ln

terG

2 ln

tegV

al,C

onve

rsio

n :V

eryl

ongV

ecto

r;

:Rea

l;

begi

n for

Siz

elnd

ex:=

1 to

M do

be

gin if K

appa

P1

k"[S

izel

ndex

l<>

O

then

be

gin

-fo

r A

rbln

dex:

=O

to (

N+1

) do

ln

terG

1 C

Arb

lnde

xl:=

(1·S

RT

1"[S

izel

ndex

,Arb

lnde

x])*

Arb

lnde

x*D

elta

E

*Arb

lnde

x*D

elta

E;

lnte

grat

eVec

tor(

lnte

rG1,

Del

taE

,01(N

+1)

,lnt

egV

al);

C

onve

rsio

n :=

3*(1

·Lam

bda1

k

[Siz

elnd

exJ)

*lnt

egV

al

+Lam

bda1

k"

[Siz

elnd

exJ*

(1-S

RT

1"[S

izel

ndex

,N+

1J )

; U

nitH

eapC

onv1

:=U

nitH

eapC

onv1

+C

onve

rsio

n*S

izeD

ata[

Siz

elnd

ex,2

J /S

umSi

zeD

ata_

2;

end;

if K

appa

P2

k"[S

izel

ndex

]<>

O

then

be

gin

-fo

r A

rbln

dex:

=O

to (

N+1

) do

ln

terG

2CA

rbln

dexJ

:=(1

·SR

T2"

[Siz

elnd

ex,A

rbln

dexJ

)*A

rbln

dex*

Del

taE

*A

rbln

dex*

Del

taE

; ln

teg

rate

Vec

tor(

lnte

rG2

,Del

taE

,0,(

N+

1),

lnte

gV

al);

C

onve

rsio

n :=

3*(1

-Lam

bda2

k"

[Siz

elnd

ex])

*lnt

egV

al

+Lam

bda2

k"

[Siz

elnd

exJ*

(1-S

RT

2"[S

izel

ndex

,N+

1J);

U

nitH

eapC

onv2

:=U

nitH

eapC

onv2

+C

onve

rsio

n*S

izeD

ata[

Siz

elnd

ex,2

J /S

umSi

zeD

ata

2;

end;

-

end·

en

d;

'

{-·-

-··

-··

·--··

-··

--··

·-··

·--·-

-··

-··

····

·-··

····

-··

-·-

·-··

·--·-

·-·-

····

··}

P

roce

dure

Gra

ph

l_ln

itia

lise

;

var G

raph

Typ

e B

eta1

S,K

appa

P1S,

Lam

bda1

S,G

DT

S B

eta2

S,K

appa

P2S,

Lam

bda2

S O

rdSP

1S,O

rdSP

2S

Inte

ger

; S

trin

g;

Str

ing

; S

trin

g;

Page 189: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

06/1

6/19

95

15:5

1 Fi

lena

me:

U

NIT

6C1.

PAS

Page

11

Cum

Tim

eS,U

nitH

eapN

oS,V

iew

Size

ClS

begi

n init

SE

Gra

phic

s(V

alid

Dir

);

SetC

urre

ntW

indo

w(3

);

Bor

derC

urre

ntW

indo

w(1

);

SetA

xesT

ype(

O,O

>;

Sca

leP

lotA

rea(

0.0,

0.0,

1.0

, 1.2

);

Set

XY

inte

rcep

ts(0

.0,0

.0);

S

etC

olor

(2);

D

raw

XA

xis(

0.2,

1);

D

raw

YA

xis(

0.2,

1);

L

abel

XA

xisC

1,0)

; L

abel

YA

xis(

1,0)

; T

itle

XA

xisC

'Dim

ensi

onle

ss R

adiu

s');

T

itle

YA

xis(

'Dm

lss

Con

e');

T

itleW

indo

wC

'Uni

t6C

1'>

; S

tr(B

eta1

:6:3

,Bet

a1s)

; S

tr(K

appa

P1:

6:3,

Kap

paP

1S);

S

tr((

Del

taT

*Pri

nt C

rit)

:6:4

,GD

TS

);

Str(

Lam

bda1

:5:3

,Lam

bda1

S);

Str

(Ord

SP

1:5:

2,0r

dSP

1S);

S

tr(B

eta2

:6:3

,Bet

a2S

);

Str

(Kap

paP

2:6:

3,K

appa

P2S

);

Str(

Lam

bda2

:5:3

,Lam

bda2

S);

Str

(Ord

SP

2:5:

2,0r

dSP

2S);

St

r(C

umT

ime:

8:4,

Cum

Tim

eS);

S

tr(U

nitH

eapl

ndex

:2,U

nitH

eapN

oS);

S

tr(V

iew

Siz

eCl:

2,V

iew

Siz

eClS

);

:Str

ing

;

Gla

bel1

:=C

onca

t('

Bet

a1

',B

eta1

S,'

; K

appa

1 ',K

appa

P1S

,';

Lam

bda1

L

ambd

a1S,

'; O

rder

1 ',O

rdS

P1S

,';

GOT

',GD

TS)

; G

Lab

el2:

=Con

catC

' B

eta2

',B

eta2

S, '

; K

appa

2 ',K

appa

P2S,

';

Lam

bda2

L

ambd

a2S,

'; O

rder

2 ',O

rdS

P2S

);

Gla

bel3

:=C

onca

t('

Cum

Tim

e 1,C

umTi

meS

,1 •

Pro

file

s of

u

nit

hea

p '

Uni

tHea

pNoS

,' an

d si

zecl

ass

',Vie

wS

izeC

lS);

L

abel

Gra

phW

indo

wC

1,90

0,G

Lab

el1,

0,0)

; L

abel

Gra

phW

indo

wC

1,85

0,"G

Lab

el2,

0,0)

; L

abel

Gra

phW

indo

wC

160,

800,

GL

abel

3,0,

0);

for

Arb

lnde

x:=1

to

2 d

o be

gin if A

rbln

dex=

1 th

en G

raph

Typ

e:=9

els

e G

raph

Typ

e:=1

0;

SetC

urre

ntW

indo

w(G

raph

Typ

e);

Bor

derc

urre

ntW

indo

wC

1>;

Set

Axe

sTyp

e(0,

0);

Sca

leP

lotA

rea(

0.0,

0.0,

1.0

, 1.2

);

Set

XY

inte

rcep

ts(0

.0,0

.0);

S

etC

olor

(2);

D

raw

XA

xis(

0.2,

1);

D

raw

YA

xis(

0.2,

1);

L

abel

XA

xis(

1,0)

; L

abel

YA

xisC

1,0)

; T

itle

XA

xis(

1D

imen

sion

less

Rad

ius'

);

Titl

eYA

xisC

'Dm

lss

Con

e');

T

itle

Win

dow

('Uni

t6C

1');

if

Arb

lnde

x=1

then

Lab

elG

raph

Win

dow

(200

,900

,'Sm

alle

st

Siz

e F

ract

ion

•,0

,0)

else

Lab

elG

raph

Win

dow

(200

,900

,1L

arge

st S

ize

Fra

ctio

n',

0,0

);

end;

·

end;

06/1

6/19

95

15:5

1 F

ilen

ame:

U

NIT

6C1.

PAS

Page

12

(·········································································}

P

roce

dure

Gra

ph1_

Res

ults

;

var G

raph

Inde

x : I

nte

ger

;

begi

n if V

iew

Size

Cl>

M

then

be

gin Clo

sese

grap

hics

; w

rite

ln('

Gra

ph

1 D

raw

ER

RO

R');

w

rite

lnC

'You

hav

e in

stu

cted

the

Gra

phin

g R

outi

ne

to g

raph

th

e co

nv

ersi

on

');

wri

teln

('cu

rves

of

a si

ze c

lass

whi

ch

does

no

t ex

ist.

');

wri

teln

C'R

espe

cify

= V

iew

size

Cla

ss

in D

ecla

rati

on

s se

cti

on

');

read

ln;

end·

fo

r1

Gra

phln

dex:

=1

to 3

do

begi

n if G

raph

lnde

x=1

then

be

gin Siz

elnd

ex:=

Vie

wS

izeC

l;

Set

Cur

rent

Win

dow

(3);

en

d el

se i

f G

raph

lnde

x=2

then

be

gin Siz

elnd

ex:=

M;

Set

Cur

rent

Win

dow

(9);

en

d el

se

begi

n Siz

elnd

ex:=

1;

Set

Cur

rent

Win

dow

(10)

; en

for1

Arb

lnde

x:=O

to

(N

+1)

do D

ataS

etX

"[A

rbln

dexJ

:=A

rbin

dex*

Del

taE

; if

Kap

paP1

<>0

then

beg

in

1

for

Arb

inde

x:=O

to

(N

+1)

do

Dat

aSet

Y"[

Arb

lnde

xJ:=

AR

T"[

Siz

elnd

ex,A

rbln

dexJ

; L

ineP

lotD

ata(

Dat

aSet

X",

Dat

aSet

Y",

(N+

2),3

,0);

fo

r A

rbin

dex:

=O

to (

N+1

) do

D

ataS

etY

"[A

rbln

dexJ

:=S

RT

1"[S

izel

ndex

tArb

lnde

xJ;

Lin

ePlo

tDat

a(D

ataS

etX

",D

ataS

etY

",(N

+2)

,),0

);

end·

if

Kap

paP2

<>0

then

beg

in

for

Arb

inde

x:=O

to

(N

+1)

do

Dat

aSet

Y"[

Arb

lnde

xJ:=

AR

T"[

Siz

elnd

ex,A

rbin

dexJ

; L

ineP

lotD

ata(

Dat

aSet

X",

Dat

aSet

Y",

(N+

2),3

,0);

fo

r A

rbin

dex:

=O

to C

N+1

) do

D

ataS

etY

"[A

rbln

dexJ

:=

SR

T2"

[Siz

eind

ex,A

rbln

dexJ

; L

ineP

lotD

ata(

Dat

aSet

x·,o

ataS

etY

",(N

+2)

,4,2

);

end·

en

' en

d;

'

(===

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

==}

Pro

cedu

re E

xecu

te_U

nit6

C1;

begi

n clrs

cr;

Page 190: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

06/1

6/19

95

15:5

1 Fi

lena

me:

U

NIT

6C1.

PAS

Page

13

Gra

ph1_

1nit

iali

se;

Rep

eats

:=O

; Fl

ag1

:=O

; Pl

ot_V

ar:=

O;

Gue

ss_S

RT

sP1;

Gra

ph1_

Res

ults

;

whi

le (

Rep

eats

<lt

erat

ions

) an

d C

AR

T.[1

,N+1

J>FC

onc_

Tol

) do

be

gin whi

le

CFl

ag1=

0)

do

begi

n Cal

e AR

TP1

and

SRTs

P1C

; Ch

ecK

Con

verg

ence

; .R

eGue

ss

SRTs

P1;

end;

-

Plo

t_V

ar:=

Plo

t_V

ar+

1;

if P

lot

Var

=P

rint

Cri

t th

en

begi

n· -

-P

lot

Var

:=O

; G

rapF

i1_R

esul

ts;

end;

Upd

ate_

AR

T_an

d_SR

Ts;

Gue

ss

SRTs

P1;

Flag

1T=O

; R

epea

ts:=

Rep

eats

+1;

end;

Gra

ph 1

Res

ults

; C

alc_

Con

vers

ion;

end;

end.

{===

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

==}

Page 191: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

1/19

95

09:0

5 Fi

lena

me:

M

ODEL

6C2.P

AS

Page

Prog

ram

Mod

el6C

2;

{Mod

el6C

2.

{ *T

his

prog

ram

is

a c

ode

for

heap

l~aching

anal

ysi

s.

*Inc

orpo

rate

s un

stea

dy s

tate

flo

w.

} } } } }

{ { {

*Use

s U

nit6

C2

whi

ch

is a

mod

ifie

d fo

rm

of

the

chem

ical

CS

TR

mod

el.

*Mod

el6C

2 v

alid

for

var

iab

le o

rder

kin

etic

s.

{Cod

ed:

Gra

ham

Dav

ies.

}

{ D

epar

tmen

t of

C

hem

ical

E

ngin

eeri

ng.

} {

Uni

vers

ity

of

Cap

e To

wn.

}

{ 6

Mar

ch

1995

. }

{ 6

June

19

95.

Upd

ated

. (G

MO)

}

{===

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

==}

{Dec

lara

tion

s:

}

uses

crt

,std

hdr,

gj,g

raph

,wor

lddr

,seg

raph

,int

egra

t,M

2C1B

rent

Roo

ts,U

nit6

C2;

cons

t

var {*

**T

hese

are

the

par

amet

ers

app

liab

le t

o th

e co

lum

n.**

****

****

****

****

}

Col

leng

th

=1.

76;

Col

Voi

dage

=D

.498

; S

atF

rac

=0.

361;

Glo

blJe

tFac

=

1.0;

{Col

umn

leng

th.

(m)

} {V

oida

ge o

f th

e co

lum

n.

} {F

ract

ion

of

the

void

spa

ce f

ille

d w

ith

flu

id.

} {A

ssum

ed

to b

e co

nsta

nt

in t

ime.

ie

Doe

s no

t ch

ange

} {w

ith a

cha

nge

in t

he f

low

rate

. }

{Glo

bal

wet

ting

fa

cto

rs o

f th

e p

art

icle

s.

}

{***

The

se a

re c

olum

n nu

mer

ical

m

etho

d pa

ram

eter

s.**

****

****

****

****

****

}

NoU

ni tH

eaps

=5;

{N1.1

nber

of

un

it h

eaps

. }

Col

Del

taE

=1

/NoU

nitH

eaps

;

uSta

r =

1/86

400;

{Ref

eren

ce s

up

erfi

cial

v

elo

city

. E

quiv

alen

t to

1m

} {i

n 2

4 ho

urs.

}

Spe

cCol

lter

s=1;

GfM

ax X

Gf

Max

::::v

=1.

0;

=1. O

'; {M

axim

um x

-val

ue f

or

conv

ersi

on g

raph

s.

{Max

imum

y-v

alue

fo

r co

nver

sion

gra

phs.

} }

{***

Oth

er

info

rmat

ion

requ

ired

.***

****

****

****

****

****

****

****

****

****

}

Val

idO

ir

=1F:

\TP6

\MO

DEL

61;{

Val

id d

irec

tory

for

gra

phic

s d

riv

ers.

}

{***

****

****

****

****

****

****

****

****

****

****

****

****

****

****

****

****

**}

Sup

Vel

Fil

e Su

pVel

Oat

a IJ

atch

Size

OT

Tex

t;

arra

y[1

•. 2

,1 •

• 2]

of D

oubl

e;

arra

yC1

.. m

axcl

of

In

teg

er;

lntL

engt

hCri

t,ln

tLen

gth,

Col

Del

ta t

,Col

Del

taT

,Arb

Val

ue

Hol

dCon

v1,H

oldC

onv2

-

. N

umsu

bint

,Tim

eCou

nter

C

onti

nue,

Col

lter

s

Dou

ble;

D

oubl

e;

Inte

ger

; In

teg

er;

07/3

1/19

95

09:0

5 F

ilen

ame:

M

OD

EL6C

2.PA

S Pa

ge

2

AR

TBTC

,SR

T1B

TC,S

RT2

BTC

,Tot

Hea

pCon

v1,T

otH

eapC

onv2

T

imeV

ecto

r T

otH

eapA

RT

Vec

,Tot

Hea

pSol

SRT

1Vec

, Tot

Hea

pSol

SRT

2Vec

OT

fo

r IJ

atch

Siz

e co

nvR

esul

ts

·ver

yLon

gVec

tor;

·v

eryL

ongV

ecto

r;

"Sho

rtV

ecto

r;

"Sqr

Mat

; T

ext;

{===

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

==}

Pro

cedu

re

lnit

iali

se_

Var

iou

s_V

aria

ble

s;

begi

n Vo

lliq

T

otV

olP

art

:=C

olD

elta

E*C

olV

oida

ge*C

olL

engt

h*S

atF

rac;

:=

Col

Del

taE

*(1-

Col

Voi

dage

)*C

olle

ngth

*Glo

blJe

tFac

;

Cum

Tim

e =O

; U

nitH

eapC

onv1

=O

; U

nitH

eapC

onv2

=O

; C

oll

ters

=O

; T

imeV

ecto

r"[O

] =O

; en

d;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--)

Pro

cedu

re

Init

iali

se_

Su

per

fici

al_

Vel

oci

ty_

Fil

e;

begi

n assi

gn(S

upV

elF

ile,

'Sup

Vel

Fi.

Dat

');

rese

t(S

upV

elF

ile)

; S

upV

elD

ata[

1, 1

1:=

0;

SupV

elD

ataC

112l

:=O

; re

ad(S

upV

elF

1le,

Sup

Vel

Dat

aC2,

1l);

re

ad(S

upV

elF

ile,

Sup

Vel

Dat

a[2,

2]);

1

Intl

engt

hCri

t:=

Col

Voi

dage

*Col

Del

taE

*Col

Len

gth;

en

d;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re C

ol_l

niti

al_C

ondi

tion

s;

,

begi

n for

Arb

lnde

x:=O

to

max

c do

be

gin Tot

Hea

pAR

TV

ec"[

Arb

lnde

x]

=O

Tot

Hea

pSol

SRT

1Vec

"[A

rbln

dex]

=O

T

otH

eapS

olSR

T2V

ec"[

Arb

lnde

x]

=O

end;

Tot

Hea

pAR

TV

ec"[

1]:=

1;

for

Arb

lnde

x:=O

to

max

v do

be

gin AR

TBTC

"[A

rbin

dex]

:=

O;

SRT

1BT

C"[

Arb

inde

xl:=

O;

SRT

2BT

C"[

Arb

lnde

xl:=

O;

Tot

Hea

pcon

v1"C

Arb

lnde

xJ :=

O;

Tot

Hea

pCon

v2"[

Arb

lnde

xJ:=

O;

end;

en

d;

{***

Impo

sed

BC

for

heap

. }

{---

---·

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

---}

Q

Q..

(1) ~ -· ~ ~ :;·

8' .., ~ Q

.. (1

) - °' (1 N ~ r:n .

Page 192: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

1/19

95

09:0

5 Fi

lena

me:

M

ODEL

6C2.P

AS

Page

3

Pro

cedu

re G

ener

ate_

Uni

tHea

pDat

aFil

es;

{Thi

s pr

oced

ure

is u

sed

to g

ener

ate

the

Uni

tHea

pDat

aFil

es.

{nam

ed M

6C1H

1 th

roug

h to

M6C

1HX.

var U

nitH

eapN

oS,F

ileN

ame

Hea

pFil

e

begi

n for

Uni

tHea

plnd

ex:=

1 to

NoU

nitH

eaps

do

be

gin Str

(Uni

tHea

plnd

ex,U

nitH

eapN

oS);

Fi

leN

ame:

=Con

cat(

1M

6ClH

1,U

nitH

eapN

oS,1

.Dat

');

assi

gn(H

eapF

ile,

Fil

eNam

e);

rew

rite

(Hea

pFil

e);

for

Siz

elnd

ex:=

l to

M do

be

gin fo

r A

rbln

dex:

=O

to N

+1

do

begi

n

The

fi L

es

are

} }

:Str

ing

; :T

ext;

wri

te(H

eapF

ile,

AR

T"[

Siz

elnd

ex,A

rbln

dexJ

,' ')

; w

rite

(Hea

pFil

e,S

RT

l"[S

izel

ndex

,Arb

lnde

xl,'

');

wri

teln

(Hea

pFil

e,S

RT

2"C

Siz

elnd

ex,A

rbln

dexl

);

end·

w

rite

ln(H

eapF

ile)

; en

d;

',Uni

tHea

pCon

v2);

w

rite

ln(H

eapF

ile,

Uni

tHea

pCon

vl,'

wri

teln

(Hea

pFil

e);

wri

teln

(Hea

pFil

e,'C

umT

ime

1,C

umTi

me)

; cl

ose(

Hea

pFil

e);

end·

en

d;

'

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re R

ead_

AR

T_an

d_SR

Ts;

var U

nitH

eapN

oS,F

ileN

ame

Hea

pFil

e

begi

n Str

(Uni

tHea

plnd

ex,U

nitH

eapN

oS);

Fi

leN

ame:

=Con

cat(

1M

6ClH

1,U

nitH

eapN

oS,1

.Dat

1);

assi

gn(H

eapF

ile,

Fil

eNam

e);

rese

t(H

eapF

ile)

; fo

r S

izel

ndex

:=l

to M

do

begi

n for

Arb

lnde

x:=O

to

N d

o be

gin read

(Hea

pFil

e,A

RT

"CS

izel

ndex

,Arb

lnde

xJ);

re

ad(H

eapF

ile

SR

T1"

[Siz

elnd

ex,A

rbln

dexl

);

read

ln(H

eapF

ile,

SR

T2"

[Siz

elnd

ex,A

rbln

dexJ

);

end;

re

ad(H

eapF

ile,

Arb

Val

ue);

A

RT

"CSi

zeln

dex,

N+l

J:=T

otH

eapA

RT

Vec

·cun

itHea

plnd

exJ;

re

ad(H

eapF

ile

SRT

1"C

Size

lnde

x,N

+1J)

; re

adln

(Hea

pFil

e,S

RT

2"[S

izel

ndex

,N+

1J);

en

d;

:Str

ing

; :T

ext;

07/3

1/19

95

09:0

5 F

ilen

ame:

M

OD

EL6C

2.PA

S Pa

ge

4

read

ln(H

eapF

ile,

Hol

dCon

v1;H

oldC

onv2

);

clos

e(H

eapF

ile)

;

end;

{-------------------------~-----------------------------------------------}

Pro

cedu

re W

rite_

AR

T_a

nd_S

RT

s;

var U

nitH

eapN

oS,F

ileN

ame

Hea

pFil

e

begi

n Str

(Uni

tHea

plnd

ex,U

nitH

eapN

oS);

Fi

leN

ame:

=Con

cat('

M6C

1H1,U

nitH

eapN

oS,1

.Dat

1);

assi

gn(H

eapF

ile,

Fil

eNam

e);

rew

rite

(Hea

pFil

e);

for

Siz

elnd

ex:=

l to

M do

be

gin fo

r A

rbln

dex:

=O

to N

+1

do

begi

n if A

RT

"[Si

zeln

dex,

Arb

lnde

xJ>

FCon

c T

ol

then

w

rite

(Hea

pFil

e,A

RT

"CS

izel

ndex

,Arb

inde

xl,'

else

wri

te(H

eap

Fil

e,0

.00

0,'

');

if S

RT

l"[S

izel

ndex

,Arb

lnde

xJ>

SC

onc

Tol

then

w

rite

(Hea

pFil

e,S

RT

1"[S

izel

ndex

,Arb

lnde

xl,'

else

wri

te(H

eap

Fil

e,0

.00

0,'

'>;

if S

RT

2"[S

izel

ndex

,Arb

lnde

xJ>

SCon

c To

l th

en

wri

teln

(Hea

pFil

e,S

RT

2"[S

izel

ndex

,Arb

lnde

xJ)

else

wri

teln

(Hea

pFil

e,0.

000)

; en

wri

teln

(Hea

pF

ile)

;

I )

:Str

ing

; :T

ext;

I)

end·

w

rite

ln(H

eapF

ile,

Uni

tHea

pCon

v1,'

wri

teln

(Hea

pFil

e);

wri

teln

(Hea

pFil

e,'C

umT

ime

clos

e(H

eapF

i le)

; U

nitH

eapC

onv1

:=0;

U

nitH

eapC

onv2

:=0;

',Uni

tHea

pCon

v2);

• ,C

umtim

e);

end;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re D

eter

min

e_M

axim

um_D

elta

T_f

n_Si

ze;

begi

n for

Uni

tHea

plnd

ex:=

1 to

NoU

nitH

eaps

do

begi

n for

Siz

elnd

ex:=

1 to

M do

end;

DT

for

wat

chS

ize·

cuni

tHea

plnd

ex,S

izei

ndex

J:=

Max

Del

taT

-

*Siz

eDat

a[S

izel

ndex

,1J*

Siz

eDat

a[S

izel

ndex

,1J

/Siz

eDat

a[M

,1l/

Siz

eDat

a[M

,1l;

for

Uni

tHea

plnd

ex:=

1 to

NoU

nitH

eaps

do

Wat

chSi

zeD

T[U

nitH

eapl

ndex

J :=

M;

end;

Page 193: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

1/19

95

09:0

5 Fi

lena

me:

M

ODEL

6C2.P

AS

Page

5

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re D

eter

min

e_C

orre

spon

ding

_Col

Del

taT

;

{Thi

s pr

oced

ure

uses

th

e m

etho

d of

ch

arac

teri

stic

s fo

de

term

ine

the

} {p

rogr

essi

on i

n tim

e fo

r a

give

n C

harC

olD

elta

E.

It a

llow

s fo

r un

stea

dy

} {

stat

e fl

ow.

}

begi

n lntl

eng

th

:=O

; C

olD

elta

t:=

O;

whi

le

Intl

engt

h<>

Intl

engt

hCri

t do

beg

in

if E

OFC

SupV

elFi

le)

then

beg

in

clos

eseg

raph

ics;

w

rite

ln('

Insu

ffic

ien

t D

ata

in t

he S

up

erfi

cial

Vel

ocit

y D

ata

Fil

e to

');

wri

teln

(•ex

ecut

e th

e re

quir

ed n

umbe

r of

it

era

tio

ns.

');

wri

teln

('P

rese

nt

num

ber

of

iter

atio

ns:

=

',Tim

eCou

nter

);

Con

tinue

:=O

; In

tlen

gth

:=In

tlen

gth

Cri

t;

read

ln;

' en

Intl

engt

h:=

Intl

engt

h+(S

upV

elD

ata[

2, 1

J-S

upV

elD

ataC

1,1J

)*S

upV

elD

ataC

2,2l

; C

olD

elta

t:

=C

olD

elta

t+

(Sup

Vel

Dat

a[2,

1]-

Sup

Vel

Dat

a[1,

1J);

If

In

tlen

gth>

Intl

engt

hCri

t th

en b

egin

A

rbV

alue

:=In

tlen

gth-

Intl

engt

hCri

t;

Col

Del

ta t

:=C

olD

elta

t-

Arb

Val

ue/S

upV

elD

ataC

2,2l

; In

tLen

gtfi

:=In

iLen

gthe

rit;

S

upV

elD

ata[

1,1J

:=S

upV

elD

ataC

2,1J

-Arb

Val

ue/S

upV

elD

ata[

2,2l

; S

upV

elD

ata[

1,2J

:=S

upV

elD

ata[

2,2l

; en

d el

se b

egin

·

SupV

elD

ata[

1, 1

] :=

SupV

elD

ataC

2, 1

l;

SupV

elD

ata[

112J

:=

Sup

Vel

Dat

a[2,

2J;

read

(Sup

Vel

F1l

e,

SupV

elD

ataC

2, 1

J);

read

(Sup

Vel

Fil

e,

Sup

Vel

Dat

a[2,

2J)

end·

en

' C

olD

elta

T:=

Col

Del

ta t

*uS

tar/

Col

leng

th;

Cum

Tim

e:=C

umTi

me+

CoT

Del

taT;

en

d;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re D

eter

min

e_A

ppro

pria

te_R

ef_S

ize_

Cla

ss_D

elta

T;

begi

n Siz

eind

ex:=

Wat

chS

izeD

T[U

nitH

eapi

ndex

J;

Iter

atio

ns:=

INT

CC

olD

elta

T/C

DT

fo

r W

atch

Siz

e·cu

nitH

eapi

ndex

,Siz

eind

exJ)

) +1

--

Del

taT

:=C

olD

elta

T/I

tera

tion

s;

wri

teln

CS

izei

ndex

);

end;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re C

heck

_Whe

ther

_Wat

chS

ize_

Sti

ll_V

alid

;

var Fl

ag

Inte

rG1

Inte

gVal

begi

n

Inte

ger

; ve

rrL

ongV

ecto

r;

Rea

;

07/3

1/19

95

09:0

5 F

ilen

ame:

M

OD

EL6C

2.PA

S Pa

ge

6

Siz

eind

ex:=

Wat

chS

izeD

TC

Uni

tHea

pind

exJ;

Fl

ag:=

O;

if A

RT

-[S

izel

ndex

,NJ<

0.5*

AR

T-C

Siz

eind

ex,(

N+

1)]

then

be

gin fo

r A

rbln

dex:

=O

to N

do

begi

n if

CA

RT

-[S

izel

ndex

,Arb

lnde

xl<

0.8*

AR

T-[

Siz

elnd

ex,C

Arb

lnde

x+1)

])

or

CA

RT

·csi

zeln

dex,

Arb

lnde

xl>

1.2*

AR

T-[

Siz

elnd

ex,(

Arb

inde

x+1)

l)

then

Fla

g:=

Fla

g+1;

en

end·

'

if

Flag

=O

then

be

gin fo

r A

rbln

dex:

=O

to N

+1

do

lnte

rG1[

Arb

lnde

x]:=

AR

T-C

Siz

elnd

ex,A

rbin

dex]

; ln

teg

rate

Vec

tor(

lnte

rG1

,Del

taE

,0,(

N+

1),

lnte

gV

al);

fo

r A

rbln

dex:

=O

to N

+1

do

if

(AR

T-[

Siz

elnd

ex,A

rbin

dex]

<(0

.9*1

nteg

val)

) or

CA

RT

-CS

izel

ndex

,Arb

inde

xl>

C1.

1*1n

tegv

al))

th

en F

lag:

=1;

if

C

Flag

=O)

and

(Wat

chSi

zeD

TC

Uni

tHea

pind

exJ>

1)

then

W

atch

Size

DT

CU

nitH

eapi

ndex

l:=W

atch

Size

DT

CU

nitH

eapi

ndex

J-1;

en

d el

se i

f A

RT

-[Si

zein

dex,

N+1

J>FC

onc_

Tol

th

en D

T_f

or_W

atch

Siz

e·cu

nitH

eapl

ndex

,S

izel

ndex

] :=

2*D

T_f

or_W

atch

Siz

e"[U

nitH

eapl

ndex

,Siz

elnd

exl;

end;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re U

pOat

e_T

otH

eapC

onv;

begi

n Tot

Hea

pCon

v1·c

coL

iter

sl :

=T

otH

eapC

onv1

·cco

lite

rsJ

+Glo

bWet

Fac*

Uni

tHea

pCon

v1/N

oUni

tHea

ps;

Tot

Hea

pCon

v2·c

coL

iter

sl :=TotHeapConvz·ccolit~rsl

+Glo

bWet

Fac*

Uni

tHea

pCon

v2/N

oUni

tHea

ps;

end;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re U

pOat

e_T

otH

eapV

ecto

r;

begi

n Tot

Hea

pAR

TV

ec·c

unitH

eapi

ndex

] :=

AR

T-[

1,N

+1l;

Tot

Hea

pSol

SRT

1Vec

·cun

itHea

plnd

exJ:

=T

otH

eapS

olSR

T1V

ec·c

unitH

eapl

ndex

J+

(Uni

tHea

pCon

v1-H

oldC

onv1

); ·

T

otH

eapS

olSR

T2V

ec·c

unitH

eapl

ndex

l :=

Tot

Hea

pSol

SRT

2Vec

·cun

itHea

pind

ex]+

(U

nitH

eapC

onv2

-Hol

dCon

v2);

en

d;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re

Incr

emen

t_T

otH

eapV

ecto

rs_a

nd_B

TC

Vec

tors

;

begi

n AR

TB

TC

-[C

ollte

rs +

1]

:=T

otH

eapA

RT

Vec

·[NoU

nitH

eaps

l; S

RT

1Brc

·cco

Lit

ers

+1J:

=Glo

bWet

Fac*

CT

otH

eapS

olSR

T1V

ec·c

NoU

nitH

eaps

]);

SR

T2B

rc·c

coll

ters

+1l

:=G

lobW

etFa

c*(T

otH

eapS

olSR

T2V

ec·c

NoU

nitH

eaps

l);

for

Arb

inde

x:=N

oUni

tHea

ps d

ownt

o 2

do

begi

n Tot

Hea

pArt

Vec

·[A

rbln

dexl

:=T

otH

eapA

rtV

ec·[

Arb

inde

x-1]

; T

otH

eapS

olSR

T1V

ec·[

Arb

lnde

x]:=

Tot

Hea

pSol

SRT

1Vec

·cA

rbln

dex-

1l;

Tot

Hea

pSol

SRT

2Vec

·[A

rbin

dexJ

:=T

otH

eapS

olSR

T2V

ec·c

Arb

lnde

x-1J

;

Page 194: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

1/19

95

09:0

5 Fi

lena

me:

M

ODEL

6C2.P

AS

Page

7

end·

T

otH

eapA

rtV

ec"[

1] :

=1;

T

otH

eapS

olSR

T1V

ec"[

1J:=

O;

Tot

Hea

pSol

SRT

2Vec

·[1J:

=O;

end;

(---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re G

raph

_Con

vers

ion_

and_

BT

C_C

urve

s;

begi

n init

SE

Gra

phic

s(V

alid

Dir

);

Set

Cur

rent

Yin

dow

(2);

B

orde

rCur

rent

Yin

dow

C1>

; S

etA

xesT

ype(

0,0)

; .

Sca

leP

lotA

rea(

0.0,

0.0,

CT

imeV

ecto

r·cc

ollt

ers]

),G

fMax

Y);

{**

*}

Set

XY

lnte

rcep

ts(0

.0,0

.0);

-

Set

Col

or(2

);

Dra

wX

Axi

sCC

Tim

eVec

tor"

[Col

lter

s]/5

), 1

);

{*

**

}

Dra

wY

Axi

s((G

fMax

Y/5

), 1

);

Lab

elX

Axi

sC1,

0);-

Lab

elY

Axi

sC1,

0);

Titl

eXA

xisC

'Dm

lss

Tim

e CD

mlss

Ti

me=

Ctim

e *

uS

tar)

/Co

llen

gth

');

Tit

leY

Axi

sC'F

rac.

C

onv.

an

d BT

C C

urve

s');

T

itleY

indo

w('M

odel

6C2

1);

Lab

elG

raph

Yin

dow

C1,

930,

GL

abel

1,0,

0);

Lab

elG

raph

Yin

dciw

C1,

900,

Gla

bel2

,0,0

);

for

Arb

inde

x:=O

to

Co

llte

rs

do D

ataS

etX

"[A

rbln

dexl

=T

imeV

ecto

r· [

Arb

lnde

xl;

for

Arb

lnde

x:=O

to

Co

llte

rs

do D

ataS

etY

"[A

rbln

dex]

=

Tot

Hea

pCon

v1"[

Arb

lnde

xl;

Lin

ePlo

tDat

a(D

ataS

etX

",D

ataS

etY

-,C

Col

lter

s +

1),

5,0

) fo

r A

rbln

dex:

=O

to C

oll

ters

do

Dat

aSet

Y"[

Arb

lnde

xl

=T

otH

eapC

onv2

"[A

rbln

dexl

; L

ineP

lotD

ata(

Dat

aSet

x·,o

ataS

etY

-,(C

oll

ters

+1

),4

,0)

for

Arb

lnde

x:=O

to

Co

llte

rs

do D

ataS

etY

"[A

rbln

dexl

=A

RT

BT

C"[

Arb

lnde

xl;

Lin

ePlo

tDat

a(D

ataS

etx"

,Dat

aSet

Y-,

(Col

lter

s +

1),

3,1

) fo

r A

rbln

dex:

=O

to C

oll

ters

do

Dat

aSet

Y"[

Arb

lnde

x]

=SR

T1B

TC

"[A

rbln

dexJ

; L

ineP

lotD

ata(

Dat

aSet

x" ,D

ataS

etY

",(C

ollt

ers

+1

),5

,1)

for

Arb

lnde

x:=O

to

Co

llte

rs

do D

ataS

etY

"[A

rbln

dexl

=S

RT

2BT

C"[

Arb

lnde

xl;

Lin

ePlo

tDat

a(D

ataS

etx·

,oat

aSet

Y-,

CC

ollt

ers

+1)

,4, 1

)

end;

{===

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

==}

(MAI

N PR

OGRA

M:

} (=

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

} be

gin

~

new

(Bet

a1

k);

new

CK

appa

P1_k

); ne

w(K

appa

s1_k

);

new

(Lai

nbda

1 k)

; ne

w(C

ontR

atio

V1)

; ne

w(A

RT)

; ne

w(S

RT

1);

new

CSR

T2);

new

(Dat

aSet

X);

new

(Bet

a2

k);

new

CK

appa

P2_k

); ne

w(K

appa

S2_k

); ne

w(L

ambd

a2

k>;

new

CC

ontR

atio

V2)

; ne

w(A

RTP

1);

new

CSR

T1P1

); ne

w(S

RT2

P1 )

; ne

wC

Dat

aSet

Y);

new

CD

elta

T_k

);

new

(SR

T1P1

C);

new

CSR

T2P1

C);

07/3

1/19

95

09:0

5 F

ilen

ame:

M

OD

EL6C

2.PA

S Pa

ge

8

new

CA

Mat

rix);

new

(AR

TBTC

); ne

wC

TotH

eapA

RTV

ec);

new

(Tot

Hea

pCon

v1);

ne

wC

DT

_for

_Yat

chSi

ze);

new

(Aln

vers

e);

new

(SR

T1B

TC);

new

(Tot

Hea

pSol

SRT

1Vec

);

new

(Tot

Hea

pCon

v2>;

assi

gn(C

onvR

esul

ts,'C

onvR

esul

ts.D

at')

; re

wri

te(C

onvR

esul

ts);

clos

e(C

onvR

esul

ts);

lnit

iali

se_

Var

iou

s_V

aria

ble

s;

Siz

e D

istr

ibu

tio

n I

nit

iali

sati

on

; C

onta

min

ant

Loc

atio

n In

itia

lisa

tio

n;

Det

erm

ine_

Mod

el_P

aram

eter

s_fn

_siz

e;

lnit

iali

se_

Su

per

fici

al_

Vel

oci

ty_

Fil

e;

Col

In

itia

l C

ondi

tion

s;

Par

ticl

e In

itia

l C

ondi

tion

s;

Gen

erat

e=U

nitH

eapo

ataF

iles

;

Det

erm

ine_

Max

imum

_Del

taT

_fn_

Size

;

whi

le C

ollt

ers<

Spe

cCol

lter

s do

be

gin Co

llte

rs:=

Co

llte

rs+

1;

Det

erm

ine_

Cor

resp

ondi

ng_C

olD

elta

T;

Tim

eVec

tor"

[Col

lter

s] :=

Cum

Tim

e;

for

Uni

tHea

plnd

ex:=

1 to

NoU

nitH

eaps

do

be

gin Rea

d AR

T an

d,SR

Ts;

if

AR

T"[

l,N+l

l>FC

onc

Toi

then

be

gin

-C

lose

segr

aphi

cs;

new

(SR

T2B

TC);

new

(Tot

Hea

pSol

SRT

2Vec

);

new

CT

imeV

ecto

r);

Det

erm

ine

App

ropr

iate

Ref

S

ize

Cla

ss D

elta

T;

Det

erm

ine-

Del

taT

fn

Siz

e;-

--

Exe

cute

Uni

t6C

2;-

-C

heck

_Yne

ther

_Yat

chS

ize_

Sti

ll_V

alid

; en

UpD~te_TotHeapConv;

UpD

ate

Tot

Hea

pVec

tor;

Y

rite_

AR

T_a

nd_S

RT

s;

end;

lncr

emen

t_T

otH

eapV

ecto

rs_a

nd_B

TC

Vec

tors

;

Ass

ign(

Con

vRes

ults

,'Con

vRes

ults

.Dat

');

App

end(

Con

vRes

ults

);

Yri

teln

(Con

vRes

ults

,Tim

eVec

tor"

[Col

lter

sl :

8:4

,1

,Tot

Hea

pCon

v1"[

Col

lter

s]:8

:4);

C

lose

(Con

vRes

ults

);

end;

Gra

ph_C

onve

rsio

n_an

d_B

TC

_Cur

ves;

read

lnC

Har

dCop

y);

if H

ardC

opy=

1 th

en S

cree

nD

um

p(3

,0,2

,1.5

,1.5

,0,1

,0,e

rro

r);

Page 195: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

~

w ro ~ ~ II

II II II II II II II II II II II

w < ~ II N II u II ~ I ~ w 0 0 ~

w E ro c w

~ ~ u 0

~ ~ ~ I 0 ro II

~ II m II ~ w II ~ ~ II ~ w II

~ II 0 II

~ II ~ u

~ II II

~ c II 0 w ~

Page 196: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

1/19

95

09:0

4 F

ilen

ame:

U

NIT

6C2.

PAS

Page

1

Uni

t U

nit6

C2;

{Uni

t6C

2.

*T

his

pro

gram

is

sim

ilar

to

*

The

prog

ram

cal

cula

tes

the

and

soli

d r

eact

ants

wit

hin

Mod

el5E

2.PA

S.

} { { { { { { { { { {

conc

entr

atio

n p

rofi

le o

f fl

uid

}

a p

arti

cle

usin

g th

e eq

uati

ons

as )

de

velo

ped

by D

ixon

. *

Th

is p

rogr

am p

rovi

des

for

var

iab

le s

oli

d r

eact

ant

ord

ers.

} )

* A

ssum

ptio

ns

in t

his

mod

el

incl

ude:

}

· ·

The

soli

d r

eact

ant

dep

osi

ts w

ithi

n th

e p

arti

cle

} re

sem

ble

thos

e on

th

e su

rfac

e.

) -

The

dep

osi

ts w

ould

bo

th

reac

t to

the

sam

e ex

ten

t }

if e

ach

wer

e ex

pose

d to

the

sam

e ac

id c

on

cen

trat

ion

}

for

the

sam

e ti

me.

}

{Cod

ed:

Gra

ham

Dav

ies.

}

{ D

epar

tmen

t of

C

hem

ical

E

ngin

eeri

ng.

} {

Uni

vers

ity

of

Cap

e To

wn.

}

{ 28

F

ebru

ary

1995

. }

{ 06

Ju

ne

1995

Upd

ated

(G

MO

). }

<===

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

==)

Inte

rfac

e

<===

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

==)

{Dec

lara

tion

s:

}

uses

crt

,std

hdr,

gj,g

raph

,wor

lddr

,seg

raph

,int

egra

t,M

2C1B

rent

Roo

ts;

cans

t <***

The

se a

re t

he p

aram

eter

s ap

pli

cab

le t

o t

he r

efer

ence

siz

e cl

ass.

**

*)

Bet

a1

= 0

.264

; K

appa

P1

= 4

.5;

Ord

SP1

= 1

.0;

Bet

a2

= 0

.0;

Kap

paP2

=

0.0

; O

rdSP

2 =

0.0

;

Voi

dage

=

0.0

1;

M

=10·

R

efSi

zeC

l =

5;'

Vie

wSi

zeC

L=S

;

{Dim

ensi

onle

ss S

toic

hiom

etri

c ra

tio

def

ined

pg

11

) {R

atio

of

reat

ion

rat

e of

so

lid

rea

ctan

t re

sid

ing

}

{wit

hin

the

part

icle

to

por

ous

dif

fusi

on

of

flu

id

} {

into

th

e p

art

icle

. D

efin

ed p

g 11

D

ixon

. }

{Rea

ctio

n or

der

of

the

soli

d i

n t

he

pore

s.

}

{Voi

dage

of

the

soli

d p

arti

lces

.(P

oro

sity

)

{Num

ber

of

size

cla

sses

. {D

efin

es t

he

refe

renc

e si

ze c

lass

. {T

he c

on

cen

trat

ion

pro

file

s of

th

is s

izec

lass

{g

raph

ed i

n gr

aph

1.

(NB

Vie

wSi

zeC

l <=

M

.)

} } } ar

e ) }

<***

The

se a

re n

umer

ical

met

hod

para

met

ers.

****

****

****

****

****

****

****

*}

N

=19;

Del

taE

=1

/(N

+1);

Max

Del

taT

=0.

001;

{Hal

f th

e nu

mbe

r of

in

teri

or

po

ints

. r=

O

and

r=R

} {n

ot

incl

uded

. {S

pace

Inc

rem

ent.

{

} C

alcu

late

d fr

om

1/(N

+1)

. (S

ince

}

R=i

*dE

and

R i

s at

po

int

N+1

.) }

{Max

imum

per

mit

ted

tim

e in

crem

ent

for

part

icle

s.

}

07/3

1/19

95

09:0

4 F

ilen

ame:

U

NIT

6C2.

PAS

Page

2

Nor

m_C

rit

=1e

-6;

Con

v C

rit

=1e

-8

scon

e To

i =

1e-4

FC

onC

:)ol

=1

e-4

Max

lter

. =

100;

Pri

nt_

Cri

t=1

;

{Con

verg

ence

cri

teri

a b

ased

on

the

norm

of

vec

tor

} <*

**

} {C

onve

rgen

ce c

rite

ria f

or

the

Bre

nt R

outi

ne.

) {D

imen

sion

less

co

nce

ntr

atio

n o

f so

lid

bel

ow w

hich

}

{Dim

ensi

onle

ss c

on

cen

trat

ion

of

flu

id r

eact

ant

} {b

elow

whi

ch

it

is a

ssum

ed

to b

e n

egig

ible

. }

{it

is

ass

umed

to

be

neg

lig

ible

. }

{Max

imum

it

erat

ion

s fo

r th

e B

rent

Rou

tine

. }

{***

Oth

er

info

rmat

ion

requ

ired

.***

****

****

****

****

****

****

****

****

****

*}

Val

idD

ir

=1F

:\T

P6\

1;{

Val

id d

irec

tory

for

gr

aphi

cs d

riv

ers.

}

{***

****

****

****

****

****

****

****

****

****

****

****

****

****

****

****

****

***}

type

var ar

ray1

= A

rray

[1 .. 5

0,1

.. 2J

of

Dou

ble;

Tot

Vol

Par

t,V

olL

iq,D

elta

T,I

tera

tion

s,C

umT

ime

Uni

tHea

pCon

v1,U

nitH

eapC

onv2

A

rbin

dex,

Siz

elnd

ex,e

rror

,Uni

tHea

plnd

ex

Rep

eats

,Plo

t_V

ar,F

lag1

,Har

dCop

y D

ataS

etX

,Dat

aSet

Y

:Dou

ble;

:D

oubl

e;

: In

teg

er;

Bet

a1

k,B

eta2

k,

Kap

paP1

k,

Kap

paP2

k,

Kap

paS1

k,

Kap

paS2

k

Lam

bda1

k,

Lam

6da2

k,

Con

tRat

ioV

1,C

ontR

atio

V2-

-

: In

teg

er;·

:"

Ver

yLon

gVec

tor;

: "

Sho

rtV

ecto

r;

:"S

hort

Vec

tor;

:"

Arr

ay1;

:"

Sqr

Mat

; :"

Sqr

Mat

; :E

xten

ded;

:E

xten

ded;

:S

trin

g;

Del

taT

K

-A

RT,

AR

fP1,

SRT1

,SR

T2,S

RT1

P1,S

RT2

P1,S

RT1

P1C

,SR

T2P1

C

AM

atri

x,A

lnve

rse

AR

TP1

CV

al,S

umSi

zeD

ata_

2,N

uSta

r L

ambd

a1,L

ambd

a2,K

appa

S1,K

appa

S2

GL

abel

1,G

labe

l2,G

Lab

el3

Siz

eDat

a :

Arr

ay[1

. .5

0, 1

. .2]

of

Rea

l;

CART

A

lpha

fn

(r)

at

tim

e T

{A

RTP1

A

lpha

fn

(r)

at

tim

e T+

1 {S

RT1

Sigm

a fn

(r)

at

tim

e T

{S

RTs

P1

Sigm

a fn

(r)

at

tim

e T+

1 (g

uess

ed)

rang

e 0

.• M

ra

nge

O •.

M

rang

e 0 ..

M

rang

e O

.• M

{S

RTs

P1C

Si

gma

fn(r

) at

ti

me

T+1

(cal

cula

ted

) ra

nge

O .. M

C

YV

ect

'Co

nst

' v

ecto

r' i

n C

rank

-Nic

olso

n m

etho

d ra

nge

O .. N

+1

{AM

atri

x M

atri

x of

Cra

nk-N

icol

son

coef

fici

ents

ra

nge

N*

N

{Dat

aSet

X

X v

ecto

r us

ed

in t

he

grap

hing

ro

uti

ne

rang

e 0 ..

N+1

0 ..

N+1

} 0 ..

N+1

} 0 ..

N+1

} 0 ..

N+1

} 0 ..

N+1

} } } }

{***

****

****

****

****

****

****

****

****

****

****

****

****

****

****

****

****

***}

Pro

cedu

re S

ize

Dis

trib

uti

on

ln

itia

lisa

tio

ni

Pro

cedu

re C

onta

min

ant

Loc

atio

n In

itia

lisa

tio

n;

Pro

cedu

re D

eter

min

e M

odel

·P

aram

eter

s fn

Siz

e;

Pro

cedu

re D

eter

min

e-D

elta

T f

n S

ize;

--

Pro

cedu

re P

arti

cle

Init

ial-

Co

nd

itio

ns;

P

roce

dure

Gue

ss

SRTs

P1;

-P

roce

dure

ReG

uess

SR

TsP1

; P

roce

dure

Cal

e C

rank

Nic

olso

n M

atri

xCva

r Y

Vec

tor

:Sho

rtV

ecto

r);

Pro

cedu

re C

alc-

AR

TP1

-and

SR

TsP1

C;

Pro

cedu

re C

hecK

_Con

verg

ence

;

Page 197: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

1/19

95

09:0

4 Fi

lena

me:

U

NIT

6C2.

PAS

Page

3

Pro

cedu

re U

pdat

e AR

T an

d SR

Ts;

Pro

cedu

re C

ale

Con

vers

ion;

Pr

oced

ure.

Gra

pn1

Init

iali

se;

Pro

cedu

re G

raph

1-R

esul

ts;

Pro

cedu

re E

xecu

te_U

nit6

C2;

f ;~[~;~~;:;1~~============================================================}

(===

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

====

==}

Fun

ctio

n P

ower

(Bas

e,P

ow:r

eal)

:Ext

ende

d;

begi

n if P

ow=O

th

en P

ower

:=1

else

if

Bas

e=O

th

en P

ower

:=O

el

se

Pow

er:=

exp(

Pow

*ln(

base

));

end;

(---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re S

ize_

Dis

trib

uti

on

_In

itia

lisa

tio

n;

(Thi

s pr

oced

ure

sets

up

the

size

dis

trib

uti

on

dat

a ar

ray

. In

itia

lly

the

}

(Siz

eOat

a ar

ray

cont

ains

ra

dius

in

form

atio

n an

d fr

acti

on

al

volu

me

} (i

nfor

mat

ion

(ie

R a

nd V

p/V

tot)

. On

out

put

it c

onta

ins

rela

tiv

e ra

dius

}

(inf

orm

atio

n an

d re

lati

ve

volu

me

info

rmat

ion

(ie R

/R

ref

and

Vp/

Vp

ref)

. }

(Id

eall

y t

his

in

form

atio

n w

ould

be

read

in

fro

m a

dat

a fi

le.

-}

var R

efR

adiu

s,V

olR

efP

art

:Dou

ble;

begi

n Si z

eDat

a [1

, 1J

= 3

7.00

e-3/

2 S

zeD

ata[

1,2l

=

58.

1/10

0 Si

zeD

ata

[2, 1

1 =

31.

25e-

3/2

S ze

Dat

a C2

, 21

= 1

5.8/

100

Si z

eDat

a C3

, 1J

= 2

2.00

e-3/

2 S

zeD

ata

C3, 2

1 =

10.

3/10

0 Si

zeD

ataC

4, 11

=

16.

10e-

3/2

S ze

Dat

a C4

, 21

=

4.1/

100

Si z

eDat

a CS

, 1J

= 1

1.3S

e-3/

2 S

zeD

ata

CS, 2

1 =

3.

2/10

0 S

izeD

ataC

6, 11

=

8.10e~3/2

s ze

Dat

a C6

, 21

=

1.8/

100

Siz

eDat

a[7,

11

=

S. 7

3e-3

/'2

S ze

Dat

a C7

, 21

=

1.3/

100

Si z

eDat

a [8

, 11

=

4.0S

e-3/

2 S

zeD

ataC

8,2l

=

1.

0/10

0 Si

zeD

ata

[9, 1

J =

2.

86e-

3/2

S ze

Dat

a C9

, 21

=

0.6/

100

Siz

eDat

a[10

, 11

=

1.18

e-3/

2 s

zeD

ata[

10,2

l =

3.

8/10

0

Vol

Ref

Par

t:=

Tot

Vol

Par

t*S

izeD

ataC

Ref

Siz

eCl,

21;

Ref

Rad

ius

:=S

izeD

ata[

Ref

Siz

ecl,

11;

Sum

Size

Dat

a_2:

=0;

for

Siz

elnd

ex:=

1 to

M do

be

gin Siz

eDat

a[S

'izel

ndex

, 11:

=S

izeD

ataC

Siz

elnd

ex,1

1/R

efR

adiu

s;

Siz

eDat

a[S

izel

ndex

,21

:=S

izeD

ata[

Siz

elnd

ex,2

l*T

otV

olP

art/

Vol

Ref

Par

t;

Sum

Size

Dat

a 2:

=Sum

Size

Dat

a 2+

Siz

eDat

aCS

izel

ndex

,21;

en

d;

--

NuS

tar:

=V

olL

iq/(

Voi

dage

*Vol

Ref

Par

t);

(Rat

io o

f vo

lum

e of

bul

k fl

uid

to

flu

id

in p

arti

cle

pore

s.

}

07/3

1/19

95

09:0

4 F

ilen

ame:

U

NIT

6C2.

PAS

Page

4

end;

(---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re C

on

tam

inan

t_L

oca

tio

n_

lnit

iali

sati

on

;

{Thi

s pr

oced

ure

is u

sed

to d

efin

e th

e co

ntam

inan

t ra

tio

vec

tor

(rati

o o

f }

{th

e su

rfac

e co

ntam

inan

t co

nce

ntr

atio

n t

o b

ulk

cont

amin

ant

con

cen

trat

ion

).}

{NO

TE:

If a

ny s

ize

clas

s of

p

arti

cles

hav

e a

surf

ace

con

cen

trat

ion

of

} (

cont

amin

ant,

th

en s

o to

o m

ust

the

refe

ren

ce s

ize

clas

s.

}

begi

n Con

tRat

oV

1"[1

1 =0

.00

Con

tRat

oV

1"C2

1 =0

.00

Con

tRat

oV

1"C

3l

=0.0

0 C

ontR

at

oV1"

C4l

=0

.00

cont

Rat

ov1

·cs1

=0

.00

Con

tRat

oV

1"[6

l =0

.00

Con

tRat

oV

1"C

7l

=0.0

0 C

ontR

at

oV1"

[8l

=0.0

0 C

ontR

at

oV1"

C9l

=0

.00

Con

tRat

ov

1·c1

01

=0.

00

Con

tRat

ov

2"C

1l

=O

Con

tRat

ov

2"C

2l

=O

Con

tRat

ov

2"C

3l

=O

Con

tRat

ov

2"C

41

=O

Con

tRat

ov

2"[S

l =O

C

ontR

at

ov2"

C6l

=O

C

ontR

at o

v2"C

71

=O

Con

tRat

ov

2"C

81

=O

Con

tRat

ov

2"[9

l =O

C

ontR

at

ov2"

C10

l =O

en

d;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re D

eter

min

e_M

odel

_Par

amet

ers_

fn_S

ize;

{Thi

s pr

oced

ure

dete

rmin

es

the

mod

el

para

met

ers

each

siz

e cl

ass

of

} {

par

ticl

es.

Not

e th

at

the

Del

taT

is

def

ined

sep

arat

ely

in

anot

her

} {p

roce

dure

. }

var F

lag1

,Fla

g2

:In

teg

er;

begi

n F

lag1

:=0;

F

lag2

:=0;

fo

r S

izel

ndex

:=1

to M

do

begi

n Lam

bda1

k"

CS

izel

ndex

l:=

Con

tRat

iov1

·csi

zeln

dexl

-

/(1+

Con

tRat

iov1

·csi

zeln

dexl

>;

Lam

bda2

k"

CS

izel

ndex

l:=

Con

tRat

iov2

-csi

zeln

dexl

-

/(1+

Con

tRat

ioV

2"[S

izel

ndex

l);

if C

ontR

atio

V1"

[Siz

elnd

exl<

>O

the

n F

lag1

:=F

lag1

+1;

if

Con

tRat

iov2

·csi

zeln

dexl

<>

O t

hen

Fla

g2:=

Fla

g2+

1;

end;

if (

((F

lag1

=1)

an

d (C

ontR

atio

v1-C

Ref

Siz

eCll

=0)

) or

((

flag

2=1)

and

(C

ontR

atio

v2"C

Ref

Siz

eCll

=0)

))

then

beg

in

clo

sese

gra

ph

ics;

w

rite

ln('

Con

tam

inan

t L

ocat

ion

Vio

loat

ion.

1);

read

ln;

end·

La

mbd

a1

=Lam

bda1

k-

[Ref

Siz

eCll

; La

mbd

a2

=Lam

bda2

-k"C

Ref

Size

Cll;

K

appa

S1

=Lam

bda1

•Kap

paP1

/(1-

Lam

bda1

);

Kap

paS2

=L

ambd

a2*K

appa

P2/C

1-L

anbd

a2);

Page 198: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

1/19

95

09:0

4 Fi

lena

me:

U

NIT

6C2.

PAS

Page

5

for

Siz

elnd

ex:=

1 to

M do

be

gin Bet

a1_k

· [S

izel

ndex

] :=

Bet

a1*(

1+C

ontR

atio

V1"

[Ref

Siz

eClJ

) /(

1+C

ontR

atio

V1"

[Siz

elnd

exJ)

; B

eta2

k"

[Siz

elnd

exJ

:=B

eta2

*(1+

Con

tRat

ioV

2"[R

efS

izeC

lJ)

-/(

1+C

ontR

atio

vz· C

Size

lnde

xJ >

; K

appa

P1

k"[S

izel

ndex

J:=

Kap

paP

1*S

izeD

ata[

Siz

elnd

ex,1

J -

*Siz

eDat

aCS

izel

ndex

,1J;

K

appa

P2

k"[S

izel

ndex

J :=

Kap

paP

2*S

izeD

ata[

Siz

elnd

ex, 1

J -

*Siz

eDat

a[S

izel

ndex

,1J;

if

Con

tRat

iov1

·csi

zeln

dexJ

=O

the

n K

appa

S1_

k.[S

izel

ndex

J :=

O e

lse

Kap

paS1

k"

[Siz

elnd

ex]

:=K

appa

S1*

Pow

er((

Con

tRat

iov1

·csi

zeln

dexJ

-

/Con

tRat

ioV

1"[R

efS

izeC

LJ)

,Ord

SP

1)

*Siz

eDat

a[S

izel

ndex

,1J;

if

Con

tRat

ioV

2"[S

izel

ndex

J=O

the

n K

appa

S2_k

"[Si

zeln

dexJ

:=O

els

e K

appa

S2

k"C

Size

lnde

xJ :

=K

appa

S2*

Pow

er((

Con

tRat

iovz

·csi

zeln

dexJ

-

/Con

tRat

ioV

2"[R

efS

izeC

lJ),

Ord

SP

2)

*Siz

eDat

a[S

izel

ndex

, 1J;

end·

~d·

, {-

-~--

----

----

----

----

----

----

----

----

----

----

----

------------------------}

Pro

cedu

re D

eter

min

e_D

elta

T_f

n_S

ize;

begi

n for

Siz

elnd

ex:=

1 to

M do

D

elta

T

k"[S

izel

ndex

, 1J

:=D

elta

T/S

izeD

ata[

Siz

elnd

ex, 1

J -

/Siz

eDat

a[S

izel

ndex

, 1J;

end;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re P

arti

cle_

lnit

ial_

Co

nd

itio

ns;

{Thi

s pr

oced

ure

uses

th

e in

itia

l co

ndit

ions

to

set

the

alph

a an

d si

gma

{vec

tors

. '

} } ar

e th

e su

rfac

e}

{Not

e th

at A

RT[

N+1

], A

RTP1

CN+1

J, SR

T1CN

+1]

and

SRT1

P1CN

+1]

{con

cent

rati

ons

of

the

liq

uid

and

so

lid

rea

ctan

ts.

begi

n for

Siz

elnd

ex:=

1 to

M do

be

gin fo

r A

rbln

dex:

=O t

o N

do

begi

n AR

T"C

Size

Jnde

x,A

rbln

dexJ

:=

O

SR

T1"

[Siz

elnd

ex,A

rbln

dexJ

:=1

SRT

2"C

Size

lnde

x,A

rbln

dexJ

:=1

SRT

1P1C

"[Si

zeln

dex,

Arb

lnde

x]

=O;

SR

T2P

1c·r

size

lnde

x,A

rbln

dexJ

=O

; en

ART

t CSi

zeln

dex,

N+1

J :=

1;

SRT1

. [Si

zel

nde

x,N

+1 J

: =1;

SR

T2"

[Siz

elnd

ex,N

+1J

:=

1;

SRT

1P1C

"[Si

zeln

dex,

Arb

lnde

xJ:=

O;

SRT

2P1C

"[Si

zeln

dex,

Arb

lnde

xl :

=0;

en

d;

end;

}

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re G

uess

_SR

TsP

1;

07/3

1/19

95

09:0

4 F

ilen

ame:

U

NIT

6C2.

PAS

Page

6

{Thi

s pr

oced

ure

prov

ides

the

in

itia

l "g

uess

" fo

r th

e it

erat

ion

. It

use

s }

{the

pre

viou

s ti

me

inte

rval

's v

alue

s as

th

e gu

ess.

}

begi

n for

Siz

elnd

ex:=

1 to

M do

be

gin fo

r A

rbln

dex:

=O

to (

N+1

) do

be

gin SR

T1P

1"[S

izel

ndex

,Arb

lnde

xJ :

=S

RT

1"C

size

lnde

x,A

rbln

dexJ

; S

RT

2P1"

[Siz

elnd

ex,A

rbln

dex]

:=

SR

T2"

[Siz

elnd

ex,A

rbln

dexJ

; en

AR

TP

1"[S

izel

ndex

,N+

1J:=

AR

T.[

Siz

elnd

ex,N

+1J

; en

· en

d;

'

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re R

eGue

ss_S

RT

sP1;

{Thi

s pr

oced

ure

prov

ides

an

upda

ted

"gue

ss"

for

the

next

it

erat

ion

. .I

t }

{use

s th

e SR

T1P1

C v

ecto

r as

the

upd

ated

gue

ss.

}

begi

n ~

for

Siz

elnd

ex:=

1 to

M do

be

gin fo

r A

rbln

dex:

=O

to (

N+1

) do

be

gin SR

T1P

1"[S

izel

ndex

,Arb

lnde

xJ:=

SR

T1P

1C"[

Siz

elnd

ex,A

rbln

dexJ

; S

RT

2P1"

CS

izel

ndex

,Arb

lnde

xJ:=

SR

T2P

1C"C

Siz

elnd

ex,A

rbln

dexJ

; en

AR

TP1

"[Si

zeln

dex,

N+1

J:=A

RT

P1C

Val

; en

d;

end·

{-

-~--

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

} P

roce

dure

Cal

c_C

rank

_Nic

olso

n_M

atri

x(va

r Y

Vec

tor

:Sho

rtV

ecto

r);

var R

ows,

Col

s

begi

n

: In

teg

er;

for

Row

s:=O

to

(N

+1)

do

begi

n for

Col

s:=O

to

(N

+1)

do A

Mat

rix"

CR

ows,

Col

sJ:=

O;

end;

AM

atri

x"[0

,0J:

=(-

6·D

elta

E*D

elta

E*S

izeD

ata[

Siz

elnd

ex,1

J*S

izeD

ata[

Siz

elnd

ex,1

J *(

Kap

paP1

csiz

elnd

exJ*

Pow

er(S

RT

1P1"

[Siz

elnd

ex,O

J,O

rdS

P1)

+K

appa

P2 K

·csi

zeln

dexJ

*Pow

er(S

RT

2P1·

csiz

elnd

ex,O

J1or

dSP2

>Y

·2*D

elta

t*D

elta

E*S

izeD

ata[

Siz

elnd

ex,1

J*S

izeD

ata[

S1z

eind

ex,1

J /D

elta

T

k·c

size

ind

ex,1

J);

AM

atri

x·co

, 1J:

=6;

-

YV

ecto

rCO

J :=

AR

T"C

Siz

elnd

ex,O

J*C

6+D

elta

E*D

elta

E*S

izeD

ata[

Siz

elnd

ex,1

J *S

izeD

ata[

Siz

elnd

ex,1

J*C

Kap

paP

1 k·

csiz

elnd

exJ

*Pow

er(S

RT

1"C

Size

inde

x,O

J,O

rdSP

T)+

Kap

paP2

k·c

size

lnde

x]

*Pow

er(S

RT

2"C

Size

inde

x,O

J,O

rdSP

2))

-·2

*Del

taE

*Del

taE

*Siz

eDat

a[S

izel

ndex

,1l

*Siz

eDat

aCS

izel

ndex

,11/

Del

taT

k·c

size

lnd

ex,1

1)

·ART

" [S

izel

ndex

,1J*

6;

-

for

Row

s:=1

to

N-1

do

Page 199: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

1/19

95

09:0

4 Fi

lena

me:

U

NIT

6C2.

PAS

Pase

7

begi

n AM

atri

x.[R

ows,

Row

s·1]

:=R

ows·

1;

·AM

atrix

.CR

ows,R

ows]

:=

·Z*R

ows·

Row

s*O

elta

E*O

elta

E*S

izeO

ata[

Size

lnde

x, 1

) *S

izeD

ata[

Siz

elnd

ex, 1

]*(K

appa

P1_

k.[S

izel

ndex

l *P

ower

(SR

T1P

1.[S

izel

ndex

,Row

sJ,O

rdSP

1)

+Kap

paPZ

k"

[Siz

elnd

exl

*Pow

er(S

RT

2P1·

csiz

elnd

ex,R

owsJ

,Ord

SP2)

) ·2

*Row

s*D

elta

E*O

elta

E*S

izeO

ata[

Siz

elnd

ex, 1

) *S

izeD

ata[

Siz

elnd

ex, 1

]/D

elta

T k

"CS

izel

ndex

, 11;

A

Mat

rix.[R

ows,

Row

s+1J

:=R

ows+

1;

-Y

Vec

torC

Row

sl :=

AR

T.C

Size

lnde

x,R

ows·

1l*C

·Row

s+1)

+

end;

AR

T.C

Size

lnde

x,R

owsl

*C2*

Row

s+R

ows*

Del

taE

*Oel

taE

*S

izeD

ataC

Si'z

elnd

ex, 1

J*S

ize0

ata[

Siz

elnd

ex, 1

1 *C

Kap

paP1

csiz

elnd

exl

*Pow

er(S

RT

1·cs

izel

ndex

,Row

sJ,O

rdSP

1)

+Kap

paP2

k"

[Siz

elnd

exl

*Pow

erC

SRT

2"[S

izel

ndex

,Row

s],O

rdSP

2))

·2*R

ows*

Del

taE

*Del

taE

*Si z

eOat

a [S

i zel

ndex

, 1'J

*Siz

eDat

a[S

izel

ndex

,1l/

Del

taT

k·c

size

lnd

ex,1

])

+AR

T"[

Size

lnde

x,R

ows+

1J*C

·Row

s·1)

;

AM

atri

x·cN

,N·1

]:=

N·1

; A

Mat

rix.C

N,N

l :=

·2*N

·N*O

elta

E*D

elta

E*S

izeO

ata[

Siz

elnd

ex,1

l *S

izeD

ata[

Size

lnde

x,1l

*CK

appa

P1

k·cs

izei

ndex

l *P

ower

(SR

T1P

1"[S

izel

ndex

,NJ,

Ord

SP1)

+Kap

paP2

k·c

size

lnde

xl

*Pow

er(S

RT

2P1.

CSi

zeJn

dex

1N

J,O

rdSP

2))·2

*N*D

eTta

E*O

elta

E

*Siz

eOat

a[S

izel

ndex

, 1l*

S1z

eDat

a[S

izel

ndex

, 1)

/Del

taT

csiz

elnd

ex, 1

1;

YV

ecto

rCN

l :=

AR

T.[S

izeJ

ndex

,N·1

l*C

·N+1

)+A

RT

·csi

zeln

dex,

Nl*

C2*

N+

N*O

elta

E*D

elta

E*S

izeO

ata[

Siz

elnd

ex,1

] *S

izeD

ata[

Size

lnde

x,1l

*CK

appa

P1

k·cs

izel

ndex

l *P

ower

CSR

T1.

[Siz

elnd

ex,N

l,Ord

SPl)

+Kap

paP2

k·c

size

lnde

xl

*Power(SRTz·csizelndex~Nl,OrdSP2))·2*N*OeTtaE*DeltaE

*Siz

eDat

a[S

izel

ndex

,11

Siz

eOat

a[S

izel

ndex

,11

/Del

taT

k"

[Siz

elnd

ex,1

J)+

AR

T·c

size

lnde

x,N

+1l

*C·N

·1)

·AR

TP1

.[Si

zeln

dex,

N+

1]*(

N+

1);

end;

{··

····

····

····

····

····

····

····

····

····

····

····

····

····

····

····

····

····

···}

P

roce

dure

Cal

c_A

RTP

1_an

d_SR

TsP1

C;

{As

it s

tand

s th

is p

roce

dure

can

cop

e w

ith

a v

aria

ble

rea

ctio

n o

rder

. T

his}

{

is d

ue

to t

he i

nclu

sion

of

the

Bre

nt R

outi

ne.

}

var M

assB

alV

al,A

Mat

Det

V

alue

AtR

oot

Out

putV

ecto

r,Y

Vec

tor

Dou

ble;

R

eal;

S

hort

Vec

tor;

begi

n {F

irst

cal

cula

te t

he A

RTP1

v

ecto

rs.

for

Siz

elnd

ex:=

1 to

M do

be

gin Cal

e C

rank

Nic

olso

n M

atri

xCY

Vec

tor)

; GaussJordanCAMatrix~,YVector,CN+1),0utputVector,Alnverse·,AMatDet);

for

Arb

lnde

x:=O

to

N d

o

}

07/3

1/19

95

09:0

4 F

ilen

ame:

U

NIT

6C2.

PAS

Page

8

end;

if O

utPu

tVec

torC

Arb

lnde

xl>F

Con

c To

l th

en

AR

TP

1·cs

izel

ndex

,Arb

lnde

xJ:=

Out

putV

ecto

r[A

rbln

dexl

el

se AR

TP

1.[S

izel

ndex

,Arb

lnde

x]:=

O;

{The

Gau

ssJo

rdan

pro

cedu

re c

alcu

late

s va

lues

for

th

e AR

T v

ecto

r fr

om

} {p

oint

0 t

o p

oint

N (

alth

ough

it

mak

es

use

of

the

N+1

th p

oin

t).

To

} {d

eter

min

e th

e N+

1 th

po

int

valu

e,

mak

e us

e of

th

e m

ass

bala

nce

of

} {

flu

id r

eact

ant

in-t

he

CSTR

. }

Mas

sBal

Val

:=O

;

for

Siz

elnd

ex:=

1 to

M do

be

gin Mas

sBal

Val

:=M

assB

alV

al·S

izeD

ataC

Size

lnde

x,2l

/2*C

Kap

paS1

csiz

elnd

exl

*SRT

1 · [

Si z

el n

dex,

(N+1

)] *

ART

· CS i

zel

nde

x, (N

+1)]

+K

appa

S1

k·cs

izel

ndex

]*S

RT

1P1·

csiz

elnd

ex,C

N+

1)l

*AR

TP

1·cs

izei

ndex

,CN

+1)

l+K

appa

S2_

k·cs

izel

ndex

l *S

RT

2·cs

izei

ndex

,CN

+1)

l*A

RT

·csi

zeln

dex,

(N+

1)J

+Kap

paS2

csiz

elnd

exl*

SR

T2P

1·cs

izel

ndex

,(N

+1)

] *A

RT

P1.

[Siz

elnd

ex,(

N+

1)])

·3*S

ize0

ata[

Siz

elnp

ex,2

l /(

Siz

e0at

a[S

izel

nd

ex,1

J*S

ize0

ata[

Siz

eln

dex

,1])

/2

*CC

AR

T.C

Size

lnde

x,(N

+1)

J+A

RT

P1·c

size

lnde

x,(N

+1)

l)

·CA

RT

.CSi

zeln

dex,

Nl+

AR

TP1

.CSi

zeln

dex,

NJ)

)/D

elta

E;

end;

AR

TP1

CV

al:=

AR

T.[1

,(N+1

)]+0

elta

T/N

uSta

r*M

assB

alV

al;

{Cal

cula

te t

he S

RTsP

1C v

ecto

rs.

Cod

e m

akes

,use

of

Bre

nt'

s M

etho

d }

{(A

no

n-l

inea

r ro

ot

find

ing

proc

edur

e)

to s

ofve

for

th

e ro

ot.

}

for

Siz

elnd

ex:=

1 to

M do

be

gin fo

r A

rbln

dex:

=O

to (

N+1

) do

beg

in

ex, 1

1,

if

(Bet

a1

k·cs

izel

ndex

l<>

O)

and

CKap

paP1

csiz

elnd

exl<

>O

) th

en

begi

n -

-if

Ord

SP1=

1 th

en

begi

n SR

T1P

1c·c

size

lnde

x,A

rbln

dexl

:=

SR

T1·

csiz

elnd

ex,A

rbln

dexl

end

*C1·

Del

taT

csiz

elnd

ex,1

l*K

appa

P1

k·cs

izel

ndex

J *B

eta1

k"

[Siz

elnd

exJ*

AR

T·c

size

inde

x,A

rbin

dexl

/C

2*C

17

Lam

bda1

csiz

elnd

exJ)

))/(

1+D

elta

T k

·csi

zeln

dex,

11

*Kap

paP1

_k.C

Size

lnde

xl*B

eta1

k

·csi

zeln

dex

f *A

RT

P1"

[Siz

elnd

ex,A

rbln

dexl

/C2*

C1·

Lam

bda1

_k·c

size

lnde

x]))

)

else

if

SRT

1P1·

csiz

elnd

ex,A

rbln

dex]

<SC

onc

Tol

th

en

SR

T1P

1c·c

size

lnde

x,A

rbln

dexl

:=S

RT

1P1·

csiz

elnd

ex,A

rbln

dexl

el

se

begi

n SR

T1P

1c·c

size

lnde

x,A

rbln

dexl

:=B

rent

Roo

ts(0

.0,1

.0,D

elta

T_k

·csi

zeln

d

end;

Kap

paP1

csiz

elnd

exJ,

Bet

a1

k·c

size

lnd

exl,

L

ambd

a1-k

·csi

zeln

dex]

,Ord

SP

l,A

RT

·csi

zeln

dex,

Arb

inde

xl,

AR

TP

1"[S

izel

ndex

,Arb

lnde

xl,S

RT

1.[S

izel

ndex

,Arb

lnde

xl,

1e·8

,100

,Val

ueA

tRoo

t,er

ror)

;

Page 200: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

1/19

95

09:0

4 Fi

lena

me:

U

NIT

6C2.

PAS

Page

9

end·

if

~Be

ta2_

k"CSiz

elnd

exJ<

>0)

and

(Kap

paP2

_k.C

Size

lnde

xJ<>

0)

then

be

gin if O

rdSP

2=1

then

be

gin SR

T2P

1C"[

Size

lnde

x,A

rbln

dexJ

:=S

RT

2"C

Size

lnde

x,A

rbln

dexJ

end

*C1·

Del

taT

k"

CSi

zeln

dex,

1J*

Kap

paP2

k"

CS'

izel

ndex

J *B

eta2

k"

CSi

zeln

dexJ

*AR

T"[

Size

lnde

x,A

rbln

dexJ

/(

2*(1

7Lam

bda2

k"

CS

izel

ndex

J)))

/(1+

Del

taT

k"[

Siz

elnd

ex,1

J *K

appa

P2

k"C

Size

lnde

xJ*B

eta2

k"[

Siz

elnd

exr

*AR

TP

1"C

size

lnde

x,A

rbln

dexJ

/(2*

C1·

Lam

bda2

_k·c

size

lnde

xJ))

)

else

if

SRT

2P1"

CSi

zeln

dex,

Arb

lnde

xJ<S

Con

c To

i th

en

SRT

1P1C

"[Si

zeln

dex,

Arb

lnde

xJ :

=SR

T2P

1"C

Size

lnde

x,A

rbln

dexJ

el

se

begi

n SRT

2P1C

"[Si

zeln

dex,

Arb

lnde

xJ :=

Bre

ntR

oots

(O.O

, 1.0

, D

elta

T

k"C

Size

lnde

x,1J

,Kap

paP2

k"

CS

izel

ndex

J,

Bet

a2 f

"[S

izel

ndex

],L

ambd

a2 k

"1S

izel

ndex

J,O

rdS

P2,

A

RT

"CSi

zeln

dex,

Arb

lnde

xJ,A

RT

P1"C

Size

lnde

x,A

rbln

dexJ

, SR

T2"

CSi

zeln

dex,

Arb

lnde

xl, 1

e·8,

100

,Val

ueA

tRoo

t,er

ror>

; en

end·

'

end·

'

end·

'

end;

'

{··

····

·-··

···-

-··-

····

·---

----

---·

-··-

----

--·-

·-··

··--

----

---·

----

----

---}

P

roce

dure

Che

ck_C

onve

rgen

ce;

{Thi

s pr

oced

ure

chec

ks w

heth

er

or n

ot

the

solu

tio

n h

as c

onve

rged

by

} {c

ompa

ring

the

gue

ssed

val

ue o

f SR

T1P1

w

ith

a ca

lcu

late

d v

alue

of

SRT1

P1.

} {A

lso

com

pare

s th

e ca

lcu

late

d v

alue

of

ARTP

1C

with

gu

esse

d va

lue

of

} CA

RTP1

. }

var N

orm

1,N

orm

2,N

orm

3 :D

oubl

e;

begi

n Norm

1 =O

; {U

sing

a n

orm

***

}

Nor

m2

=O;

Nor

m3

=O;

for

S ze

lnde

x:=

1 to

M do

be

gin fo

r A

rbln

dex:

=O

to (

N+1

) do

be

gin if (

Bet

a1

k"[S

izel

ndex

l<>

O)

and

CKap

paP1

k"

CSi

zeln

dex]

<>O

) th

en b

egin

N

orm

1:=N

orm

1+C

SRT

1P1C

"CSi

zeln

dex,

Arb

lnde

xl

-SR

T1P

1"C

Size

lnde

x,A

rbln

dexJ

)*(S

RT

1P1C

"[Si

zeln

dex,

Arb

lnde

xl

-SR

T1P

1"C

Size

lnde

x,A

rbln

dexJ

);

end

else

Nor

m1:

=0;

if C

Bet

a2

k"C

Size

lnde

xJ<>

O)

and

(Kap

paP2

k"

CSi

zeln

dex]

<>O

) th

en b

egin

No

rm2:

:Nor

m2+(

SRT2

P1C"

[Siz

elnd

e~,A

rbln

dexJ

-S

RT

2P1"

CSi

ze!n

dex,

Arb

lnde

xJ)*

CSR

T1P

1C"[

Size

lnde

x,A

rbln

dexl

-S

RT

2P1"

CSi

zeln

dex,

Arb

lnde

xJ);

en

d el

se N

orm

2:=0

;

07/3

1/19

95

09:0

4 F

ilen

ame:

U

NIT

6C2.

PAS

Page

10

end·

en

' N

oriri

3:=(

AR

TP1C

Val

-AR

TP1"

[1,

N+1

])*C

AR

TP1C

Val

-AR

TP1"

C1

N+

1l);

if

(N

orm

1<N

orm

Cri

t) a

nd

CNor

m2<

Nor

m C

rit)

an

d (N

or~<

Norm

Cri

t)

then

F

lag1

::1;

-

-en

d;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re U

pdat

e_A

RT_

and_

SRTs

;

{Thi

s pr

oced

ure

upda

tes

the

alph

a an

d si

gma

vec

tors

for

th

e ne

xt

iter

atio

n}

{b

y re

plac

ing

thei

r co

mpo

nent

s w

ith

the

alph

aT+1

an

d si

gmaT

+1

vec

tors

. }

begi

n for

Siz

elnd

ex:=

1 to

M do

be

gin fo

r A

rbln

dex:

=O

to (

N+1

) do

be

gin AR

T"[

Size

lnde

x,A

rbln

dexJ

=A

RT

P1"C

Size

lnde

x,A

rbin

dexJ

; S

RT

1"[S

izel

ndex

,Arb

lnde

xl

=S

RT

1P1"

[Siz

elnd

ex,A

rb!n

dexJ

; S

RT

2"[S

izel

ndex

,Arb

lnde

xJ

=S

RT

2P1"

[Siz

elnd

ex,A

rbln

dex]

; en

end·

'

end;

'

{---

-·--

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re C

alc_

Con

vers

ion;

{Thi

s pr

oced

ure

calc

ula

tes

the

frac

tio

nal

co

nver

sion

of

the

par

ticl

e fo

r }

{the

tim

e in

terv

al.

It u

ses

the

form

ula

on

pg.

13 D

ixon

. Th

e in

teg

rato

r}

{is

the

Qui

nn-C

urti

s ve

ctor

in

teg

rato

r.

}

var I n

terG

1 I n

terG

2 In

tegv

al,c

onve

rsio

n :V

eryL

ongV

ecto

r;

:Rea

l;

begi

n for

Siz

elnd

ex:=

1 to

M do

be

gin if K

appa

P1

k"C

Size

lnde

xJ<>

O

then

be

gin

-fo

r A

rbin

dex:

=O

to C

N+1

) do

.

Inte

rG1[

Arb

lnde

xJ:=

C1-

SR

T1"

CS

izel

ndex

,Arb

inde

xJ)*

Arb

lnde

x*D

elta

E

*Arb

lnde

x*D

elta

E;

lnte

grat

eVec

tor(

Inte

rG1,

Del

taE

,0t(

N+

1),l

nteg

Val

);

Con

vers

ion

:=3*

C1-

Lam

bda1

k

[Siz

elnd

exJ)

*lnt

egV

al

+Lam

bda1

k"

[Siz

elnd

exJ*

C1-

SR

T1"

[Siz

elnd

ex,N

+1J

);

Uni

tHea

pCon

v1:=

Uni

tHea

pCon

v1+

Con

vers

ion*

Size

Dat

a[Si

zeln

dex,

2]

/Sum

Size

Dat

a_2;

en

d;

if K

appa

P2

k"[S

izel

ndex

]<>

O

then

be

gin

-fo

r A

rbln

dex:

=O

to C

N+1

) do

ln

terG

2CA

rbln

dexJ

:=(1

-SR

T2"

[Siz

elnd

ex,A

rbln

dexJ

)*A

rbln

dex*

Del

taE

*A

rbln

dex*

Del

taE

; ln

tegr

ateV

ecto

r(ln

terG

2,D

elta

E,0

t(N

+1)

,lnt

egV

al);

C

onve

rsio

n :=

3*C

1-L

ambd

a2

k C

Siz

elnd

exJ)

*Int

egV

al

+Lam

bda2

_k"[

Size

lnde

xJ*C

1-SR

T2"

CSi

zeln

dex,

N+1

J);

Page 201: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

1/19

95

09:0

4 Fi

lena

me:

U

NIT

6C2.

PAS

Page

11

Uni

tHea

pcon

v2:=

Uni

tHea

pCon

v2+

Con

vers

ion*

Size

Oat

a[Si

zeln

dex,

2l

/Sum

Size

Dat

a_2;

en

end·

'

end;

'

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re G

raph

1_1n

itia

lise

;

var G

raph

Typ

e B

eta1

S,K

appa

P1S,

Lam

bda1

S,G

DT

S B

eta2

S,K

appa

P2S,

Lam

bda2

S O

rdSP

1S,O

rdSP

2S

Cum

Tim

eS,U

nitH

eapN

oS,V

iew

Size

ClS

Inte

ger

; st

rin

g;

Str

ing

; S

trin

g;

Str

ing

;

begi

n init

SE

Gra

phic

s(V

alid

Dir

);

SetC

urre

ntW

indo

w(3

);

Bor

derC

urre

ntW

indo

w(1

);

Set

Axe

sTyp

e(0,

0);

Sca

leP

lotA

rea(

0.0,

0.0,

1.0

, 1.2

);

Set

XY

lnte

rcep

ts(0

.0,0

.0);

S

etC

olor

(2);

D

raw

XA

xis(

0.2,

1);

D

raw

YA

xis(

0.2,

1);

Lab

elX

Axi

s(1,

0);

Lab

elY

Axi

s(1,

0);

Tit

leX

Axi

s('D

imen

sion

less

Rad

ius'

);

Tit

leY

Axi

s('D

mls

s C

one'

);

Tit

leW

indo

w('U

nit6

C2'

);

Str

(Bet

a1:6

:3,B

eta1

S);

S

tr(K

appa

P1:

6:3,

Kap

paP

1S);

S

tr((

Del

taT

*Pri

nt_C

rit)

:6:4

,GD

TS

);

Str(

Lam

bda1

:5:3

,Lam

bda1

S);

Str

(Ord

SP

1:5:

2,0r

dSP

1S);

S

tr(B

eta2

:6:3

,Bet

a2S

);

Str

(Kap

paP

2:6:

3,K

appa

P2S

);

Str(

Lam

bda2

:5:3

,Lam

bda2

S>;

Str

(Ord

SP

2:5:

2,0r

dSP

2S);

St

r(C

llllT

ime:

8:4,

Cum

Tim

eS);

S

tr(U

nitH

eapl

ndex

:2,U

nitH

eapN

oS);

S

tr(V

iew

Siz

eCl:

2,V

iew

Siz

eClS

);

Gla

bel1

:=C

onca

t('

Bet

a1

',B

eta1

S,'

; K

appa

1 1,K

appa

P1S

,';

Lam

bda1

La

mbd

a1S

•· O

rder

1 '

Ord

SP1S

•·

GO

T '

GD

TS)·

GL

abel

2:=C

onca

tC'

Bet

a2 •:s~ta2S,'i

K~ppa2

•:K~

ppaP2s,•;

Lam

bda2

L

ambd

a2S,

'; Order~

',Ord

SP

2S);

G

Lab

el3:

=C

onca

t('

CllT

ITim

e ',C

umTi

meS

1'

Pro

file

s of

un

it h

eap

' U

nitH

eapN

oS['

and

s1ze

clas

s ',V

iew

size

ClS

);

Lab

elG

raph

Win

dow

(1,9

00,G

Lab

e 1

,0,0

);

Lab

elG

raph

Win

dow

C1,

850,

GL

abel

2 0

,0)·

L

abel

Gra

phW

indo

wC

160,

800,

GL

abe[

3,0,

0);

for

Arb

lnde

x:=1

to

2 d

o be

gin if A

rbln

dex=

1 th

en G

raph

Typ

e:=9

els

e G

raph

Typ

e:=1

0;

SetC

urre

ntW

indo

w(G

raph

Typ

e>;

Bor

derC

urre

ntW

indo

w(1

);

SetA

xesT

ypeC

0,0)

· S

cale

Plo

tAre

a(0

.0,0

.0,1

.0,1

.2);

S

etX

Yln

terc

epts

(0.0

,0.0

);

07/3

1/19

95

09:0

4 F

ilen

ame:

U

NIT

6C2.

PAS

Page

12

Set

Col

or(2

);

Dra

wX

Axi

s(0.

2,1)

; D

raw

YA

xis(

0.2 01>

; L

abel

XA

xis(

1,

>;

Lab

elY

Axi

s(1,

0>;

Tit

leX

Axi

s('D

imen

sion

less

Rad

ius'

);

Tit

leY

Axi

sC'D

mls

s C

one'

>;

Tit

leW

indo

w('U

nit6

C2'

>;

if A

rbln

dex=

1 th

en L

abel

Gra

phW

indo

w(2

00,9

00,

1S

mal

lest

Siz

e F

ract

ion

',0

,0)

else

Lab

elG

raph

Win

dow

(200

,900

,'Lar

gest

Siz

e F

ract

ion

',0

,0);

en

d;

end;

{---

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

----

--}

Pro

cedu

re G

raph

1_R

esul

ts;

var G

raph

Inde

x : I

nte

ger

;

begi

n if V

iew

Size

Cl>

M

then

be

gin Clo

sese

grap

hics

; w

rite

ln('

Gra

ph 1

Dra

w

ERR

OR

');

wri

teln

('Y

ou h

ave

inst

uct

ed t

he G

raph

ing

Rou

tine

to

gra

ph

the

con

ver

sio

n')

;

wri

teln

('cu

rves

of

a si

ze c

lass

whi

ch

does

not

ex

ist.

');

wri

teln

('R

esp

ecif

y =

Vie

wS

izeC

lass

in

Dec

lara

tio

ns

sect

ion

'>;

read

ln;

end·

fo

r1

Gra

phln

dex:

=1

to 3

do

begi

n if G

raph

lnde

x=1

then

be

gin Siz

elnd

ex:=

Vie

wS

izeC

l;

Set

Cur

rent

Win

dow

(3);

en

d el

se i

f G

raph

lnde

x=2

then

be

gin Siz

elnd

ex:=

M;

Set

Cur

rent

Win

dow

(9);

en

d el

se

begi

n Siz

elnd

ex:=

1;

Set

curr

entW

indo

w(1

0);

end·

fo

r1

Arb

lnde

x:=O

to

(N

+1)

do D

ataS

etX

"[A

rbln

dex]

:=

Arb

lnde

x*D

elta

E;

if K

appa

P1<>

0 th

en b

egin

fo

r A

rbln

dex:

=O

to (

N+1

) do

D

ataS

etY

0

[Arb

lnde

x]:=

AR

T0

[Siz

elnd

ex,A

rbln

dex]

; L

ineP

lotD

ata(

Dat

aSet

X0

,Dat

aSet

Y0

,(N

+2

),3

,0);

fo

r A

rbln

dex:

=O

to (

N+1

) do

D

ataS

etY

"[A

rbln

dex]

:=S

RT

1"[S

izel

ndex

iArb

lnde

xl;

Lin

ePlo

tDat

a(D

ataS

etX

0

,Dat

aSet

Y",

(N+

2),,

,0);

en

if K

appa

P2<>

0 th

en b

egin

fo

r A

rbln

dex:

=O

to (

N+1

) do

D

ataS

etY

°CA

rbln

dexl

:=A

RT

0

[Siz

elnd

ex,A

rbln

dex]

; L

ineP

lotD

ata(

Dat

aSet

X0

,Dat

aSet

Y0

,(N

+2

),3

,0);

fo

r A

rbln

dex:

=O

to (

N+1

) do

Page 202: PREDICTION OF LEACHATE GENERATION FROM

Univers

ity of

Cap

e Tow

n

07/3

1/19

95

09:0

4 Fi

lena

me:

U

NIT

6C2.

PAS

Page

13

Dat

aSet

Y"[

Arb

lnde

x] :

=S

RT

2.[S

izel

ndex

,Arb

lnde

xl;

Lin

ePlo

tDat

a(D

ataS

etx·

,oat

aSet

Y.,

(N+

2),4

,2>

; en

· en

' ~d;

<===

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====

==}

Pro

cedu

re E

xecu

te_U

nit6

C2;

begi

n cl r

scr;

Gra

ph1_

Init

ial i

se;

Rep

eats

:=O

; Fl

ag1

:=O

; Pl

ot_V

ar:=

O;

Gue

ss_S

RTs

P1;

Gra

ph1_

R.e

sul t

s;

whi

le

(Rep

eats

<lt

erat

ions

) an

d C

AR

T.C

1,N

+1l>

FCon

c T

ol)

do

begi

n ·

-w

hile

(Fl

ag1=

0) d

o be

gin Cal

e AR

TP1

and

SRTs

P1C

; Ch

ecl<

Con

verg

ence

; .

· R

eGue

ss_S

RTs

P1;

end;

Plot~Var:=Plot_Var+1;

if P

lot

Var

=P

rint

Cri

t th

en

begi

n -

-P

lot

Var

:=O

· G

rapl

i1_R

esul

ts;

end;

Upd

ate_

AR

T_an

d_SR

Ts;

Gue

ss_S

RTs

P1;

· Fl

ag1

:=0;

Repeats:=Repeat~+1;

end;

Gra

ph1

Res

ults

; ca

lc_c

onve

rsio

n;

end;

end.

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==}

l... "

r--

----..

,_ __ "