co2 capture using dea+mdea

7/26/2019 CO2 Capture Using DEA+MDEA

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Rate-Based Model of theCO2Capture Process byDEA+MDEA AqueousSolution using AspenHYSYS


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Contents 1

Contents

Introduction ............................................................................................................ 2

1 Components ......................................................................................................... 3

2 Physical Properties ............................................................................................... 4

4 Reactions ........................................................................................................... 16

5 Simulation Approach .......................................................................................... 20

6 Simulation Results ............................................................................................. 24

References ............................................................................................................ 25


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2 Introduction

Introduction

The supplied HYSYS case CO2+H2S Capture Using DEA+MDEA.hscillustrates the use of rigorous rate-based distillation to accurately model CO2capture by a mixed DEA and MDEA aqueous solution from a gas mixture ofCO2, CH4, C2H6, C3H8, n-C4H10, i-C4H10, n-C5H12and N2. The actual fieldperformance data for an operating column from Weiland (2001)[1]were usedto specify feed conditions and specifications for the absorber.

Key features of this rigorous simulation include electrolyte thermodynamicsand solution chemistry, reaction kinetics for the liquid phase reactions,rigorous transport property modeling, rate-based multi-stage simulation withAspen Rate-Based Distillation which incorporates heat and mass transfercorrelations accounting for columns specifics and hydraulics.

The model is meant to be used as a guide for modeling the CO2captureprocess with DEA+MDEA. It may be used as a starting point for moresophisticated models for process development, debottlenecking, plant andequipment design, among others.


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1 Components 3

1 Components

The following components represent the chemical species present in theprocess:

Table 1. Components Used in the Model

ID Type Name Formula

DEA Conventional DIETHANOLAMINE C4H11NO2-1

H2O Conventional WATER H2O

CO2 Conventional CARBON-DIOXIDE CO2

H2S Conventional HYDROGEN-SULFIDE H2S

H3O+ Conventional H3O+ H3O+

OH- Conventional OH- OH-

HCO3- Conventional HCO3- HCO3-

CO3-2 Conventional CO3-- CO3-2

DEAH+ Conventional DEA+ C4H12NO2+

DEACOO- Conventional DEACOO- C5H10NO4-HS- Conventional HS- HS-

S-2 Conventional S-- S-2

MDEA Conventional METHYL-DIETHANOLAMINE C5H13NO2

MDEAH+ Conventional MDEA+ C5H14NO2+

CH4 Conventional METHANE CH4

C2H6 Conventional ETHANE C2H6

C3H8 Conventional PROPANE C3H8

C4H10-01 Conventional N-BUTANE C4H10-1

C4H10-02 Conventional ISOBUTANE C4H10-2

C5H12-01 Conventional N-PENTANE C5H12-1N2 Conventional NITROGEN N2

O2 Conventional OXYGEN O2

CO Conventional CARBON-MONOXIDE CO

H2 Conventional HYDROGEN H2


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4 2 Physical Properties

2 Physical Properties

The physical properties for the simulation were configured using AspenProperties. A pre-configured Aspen Properties file (DEA+MDEAProperties.aprbkp) has been provided. The details of the physical propertiesconfiguration are provided below.

The electrolyte NRTL method is used for liquid and RK equation of state isused for the vapor. The NRTL parameters were regressed against

CO2solubility data in aqueous DEA solutions from Maddox et al. (1987,1989)[6,7]for the sub-system CO2-DEA-H2O

CO2solubility data in aqueous MDEA solutions from Jou et al. (1982,1993)[8,9,10], Kuranov et al. (1996)[11]and Kamps et al. (2001)[12]for thesub-system CO2-MDEA-H2O

CO2solubility data in aqueous DEA+MDEA solutions from Benamor andAroua (2005)[13]for the mixed amine system CO2-DEA-MDEA-H2O systemon the basis of the NRTL parameters for the sub-systems CO2-DEA-H2Oand CO2-MDEA-H2O

H2S solubility data in aqueous DEA solutions from Barreau et al. (2006)[14]

and from Lawson and Garst (1976)[15]for the sub-system H2S-DEA-H2O H2S solubility data in aqueous MDEA solutions from Kuranov et al.

(1996)[11]and Kamps et al. (2001)[12]for the sub-system H2S-MDEA-H2O

CO2, CH4, C2H6, C3H8, n-C4H10, i-C4H10, n-C5H12, N2, O2, CO and H2areselected as Henry-components to which Henrys law is applied.The Henrysconstants are retrieved from Aspen Properties databanks for thesecomponents with water, except for those for n-C5H12with H2O, which aretaken from NIST web database. For solvents MEA and MDEA, the Henrysconstants are obtained as follows:

For CO2with DEA, regressed from CO2 solubility data[6,7]in aqueous DEA

solutions

For CO2with MDEA, regressed from CO2solubility data[8-12]in aqueous

MDEA solutions

For H2S with DEA, regressed from H2Ssolubility data[14,15]in aqueous DEA

solutions

For H2S with MDEA, regressed from H2S solubility data[11,12]in aqueous

MDEA solutions

However, we do not have any information to identify the Henrys constantsfor the hydrocarbon species with DEA or MDEA. In the reactions calculations,


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2 Physical Properties 5

the activity coefficient basis for the Henrys components (solutes) is chosen tobe Aqueous. Therefore, in calculating the unsymmetric activity coefficients(GAMUS) of the solutes, the infinite dilution activity coefficients are calculatedbased on infinite-dilution condition in pure water, instead of in mixedsolvents.

The liquid molar volume model and transport property models have beenvalidated for the sub-systems CO2-DEA-H2O and CO2-MDEA-H2O and modelparameters are regressed from literature experimental data[16-26]for thesetwo sub-systems. However, no data are found for the mixed amine systemloaded with CO2. And we did not check these properties of the DEA and/orMDEA systems loaded with H2S. Specifications of the transport propertymodels include:

For liquid molar volume, the Clarke model, called VAQCLK in AspenProperties, is used with option code 1 to use the quadratic mixing rule forsolvents.The interaction parameter VLQKIJ for the quadratic mixing rule betweenDEA and H2O is regressed against experimental DEA-H2O density datafrom Maham et al. (1994)[16], and VLQKIJ between MDEA and H2O isregressed against experimental MDEA-H2O density data from Bernal-Garcia et al. (2003)[17].

The Clarke model parameter VLCLK/1 is also regressed for mainelectrolytes (DEAH+, HCO

3), (DEAH+, DEACOO ) and (DEAH+, CO 2

3

)

against experimental density data of the CO2-DEA-H2O system fromWeiland (1998)[18]and for (MDEAH+, HCO

3) and (MDEAH+, CO 2

3) against

experimental density data of the CO2-MDEA-H2O system from Weiland(1998)[18]

For liquid viscosity, the Jones-Dole electrolyte correction model, calledMUL2JONS in Aspen Properties, is used with the mass fraction basedASPEN liquid mixture viscosity model for the solvent. There are threemodels for electrolyte correction and the DEA+MDEA model always usesthe Jones-Dole correction model. The three option codes for MUL2JONSare set to 1 (mixture viscosity weighted by mass fraction), 1 (always useJones and Dole equation when the parameters are available), and 2(ASPEN liquid mixture viscosity model), respectively.

The interaction parameters between DEA and H2O in the ASPEN liquidmixture viscosity model, MUKIJ and MULIJ, are regressed againstexperimental DEA-H2O viscosity data from Oyevaar(1989)

[19], Rinker et al.(1994)[20], Hsu and Li (1997)[21], Weiland (1998)[18], and Mandal et al.(2003)[22]. MUKIJ and MULIJ between MDEA and H2O are regressedagainst experimental viscosity data of the MDEA-H2O system from Teng etal. (1994)[23].

The Jones-Dole model parameters, IONMUB, for DEAH+and DEACOO-areregressed against CO2-DEA-H2O viscosity data from Weiland (1998)

[18];for MDEAH+, is regressed against CO2-MDEA-H2O viscosity data fromWeiland (1998)[18]; for CO 2

3

, is regressed against K2CO3-H2O viscosity

data from Pac et al. (1984)[24]; and for HCO3-, is regressed against KHCO3-

H2O viscosity data from Palaty (1992)[25].

For liquid surface tension, the Onsager-Samaras model, called SIG2ONSGin Aspen Properties, is used with its option codes being -9 (exponent in


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mixing rule) and 1 (electrolyte system), respectively. Predictions for thesub-systems CO2-DEA-H2O and CO2-MDEA-H2O are within the range of theexperimental data from Weiland (1996)[26].

For thermal conductivity, the Riedel electrolyte correction model, calledKL2RDL in Aspen Properties, is used.

For binary diffusivity, the Nernst-Hartley model, called DL0NST in AspenPlus, is used with option code of 1 (mixture viscosity weighted by massfraction).

In addition to the updates with the above transport properties, heat capacityat infinite dilution (CPAQ0) for MDEAH+, DEAH+and DEACOO-are adjusted tofit to heat capacity data from Weiland (1996)[26].

The aqueous phase heat of formation at infinite dilution and 25C (DHAQFM)for DEAH+and DEACOO-are adjusted to fit to the literature heat of solutiondata from Carson et al. (2000)[27]of the sub-system CO2-DEA-H2O. ForMDEAH+, the databank value for DHAQFM is -5.0471 x108J/kmol, whichresults in heat of solution predictions for the sub-system CO2-MDEA-H2O asshown in Figure 6b-1 together with the data from Carson et al. (2000)[27].

However, to match the temperature profile data of an plant absorber for CO2capture by aqueous MDEA solutions[28], its found that a value of -5.0x108J/kmol for DHAQFM of MDEAH+ is better. This value is used in thecurrent simulation and results in heat of solution predictions as shown inFigure 6b-2.

The estimation results of various transport and thermal properties aresummarized in Figures 1-8:

900

950

1000

1050

1100

1150

1200

0 0.1 0.2 0.3 0.4 0.5

CO2 Loading, mol/mol

Dens

ity,

kg

/m3

EXP DEA 10w t%EXP DEA 20w t%EXP DEA 30w t%EXP DEA 40w t%EST DEA 10w t%

EST DEA 20w t%EST DEA 30w t%EST DEA 40w t%

Figure 1a. Liquid Density of DEA-CO2-H2O at 298.15K, experimental datafrom Weiland (1998)[18]


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900

950

1000

1050

1100

1150

1200

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7


Dens

ity,

kg

/m3

EXP MDEA 30w t%

EXP MDEA 40w t%

EXP MDEA 50w t%

EXP MDEA 60w t%

EST MDEA 30w t%

EST MDEA 40w t%

EST MDEA 50w t%

EST MDEA 60w t%

Figure 1b. Liquid Density of MDEA-CO2-H2O at 298.15K, experimental datafrom Weiland (1998)[18]

0.1

1

10

0 0.1 0.2 0.3 0.4 0.5


Viscosity,mPaS

EXP DEA 20w t%

EXP DEA 30w t%

EXP DEA 40w t%

EST DEA 20w t%

EST DEA 30w t%

EST DEA 40w t%

Figure 2a. Liquid Viscosity of DEA-CO2-H2O at 298.15K, experimental datafrom Weiland (1998)[18]


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1.00

10.00

100.00

1000.00

0 0.1 0.2 0.3 0.4 0.5

CO2 Loading

Log

(Viscos

ity,

mPaS

)

EXP MDEA 30w t%EST MDEA 30w t%EXP MDEA 40w t%EST MDEA 40w t%EXP MDEA 50w t%EST MDEA 50w t%EXP MDEA 60w t%EST MDEA 60w t%

Figure 2b. Liquid Viscosity of MDEA-CO2-H2O at 298.15K, experimental datafrom Weiland (1998)[18]

0

10

20

30

40

50

60

70

80

90

100

0.00 0.10 0.20 0.30 0.40 0.50


Surface

Tens

ion,

mN/m

EXP DEA 10w t%EST DEA 10w t%EXP DEA 20w t%EST DEA 20w t%EXP DEA 30w t%EST DEA 30w t%EXP DEA 40w t%EST DEA 40w t%

Figure 3a. Surface tension of DEA-CO2-H2O at 298.15K, experimental datafrom Weiland (1996)[26]


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0.03

0.04

0.05

0.06

0.07

0.08

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7

CO2 Loading

Surface

Tens

ion,N

/m

EXP MDEA 30w t%EST MDEA 30w t%EXP MDEA 40w t%EST MDEA 40w t%EXP MDEA 50w t%EST MDEA 50w t%EXP MDEA 60w t%

EST MDEA 60w t%

Figure 3b. Surface tension of MDEA-CO2-H2O at 298.15K, experimental datafrom Weiland (1996)[26]

0

0.1

0.2

0.3

0.4

0.5

0.6

0 0.1 0.2 0.3 0.4 0.5 0.6


ThermalConductivity,

Wat

t/m-K

DEA 10w t%

DEA 20w t%

DEA 30w t%

DEA 40w t%

Figure 4a. Liquid Thermal Conductivity of DEA-CO2-H2O at 298.15K


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0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0 0.1 0.2 0.3 0.4 0.5


Therma

lCon

duc

tiv

ity,

Wa

tt/mK

EST MDEA 30w t%

EST MDEA 40w t%

EST MDEA 40w t%

EST MDEA 60w t%

Figure 4b. Liquid Thermal Conductivity of MDEA-CO2-H2O at 298.15K

Figure 5a. Liquid Heat Capacity of DEA-CO2-H2O at 298.15K, experimentaldata from Weiland (1996)[26]


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0

20

40

60

80

100

120

140

160

0 0.1 0.2 0.3 0.4 0.5

CO2 Loading

Hea

tCapac

ity,

J/mol-

K

EXP MDEA 30w t%

EXP MDEA 40w t%

EXP MDEA 50w t%

EXP MDEA 60w t%

EST MDEA 30w t%

EST MDEA 40w t%

EST MDEA 50w t%

EST MDEA 60w t%

Figure 5b. Liquid Heat Capacity of MDEA-CO2-H2O at 298.15K, experimentaldata from Weiland (1996)[26]

Figure 6a. Heat of Solution of DEA-CO2-H2O at 298.15K, experimental datafrom Carson et al. (2000)[27]


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Figure 6b-1. Heat of Solution of CO2in MDEA-H2O using ASPEN databankDHAQFM(MDEAH+) value (-5.0471E8J/kmol), experimental data from Carsonet al. (2000)[27]

Figure 6b-2. Heat of Solution of CO2in MDEA-H2O using DHAQFM(MDEAH+)=-

5.0E8J/kmol, experimental data from Carson et al. (2000)[27]


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Figure 7a. CO2partial pressure of DEA-CO2-H2O (DEA mass fraction = 0.20),experimental data from Maddox et al. (1989)[7]

1

10

100

1000

10000

0.1 1 10

CO2 Loading

CO2Pressure,

KPa

EXP 310.9K

EST 310.9K

EXP 338.7K

EST 338.7K

EXP 388.7K

EST 388.7K

Figure 7b. CO2Partial Pressure of MDEA-CO2-H2O (MDEA mass fraction =0.20), experimental data from Maddox et al. (1987)[6]


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0.1

1

10

100

1000

0.01 0.1 1

CO2 Loading

CO2Pressure,k

Pa

EXP 303K

EST 303K

EXP 313K

EST 313K

EXP 323K

EST 323K

Figure 7c. CO2Partial Pressure of DEA-MDEA-CO2-H2O (MDEA 1m and DEA1m), experimental data from Benamor and Aroua (2005)[13]

0.001

0.01

0.1

1

10

100

1000

10000

100000

0.001 0.01 0.1 1 10

H2S Loading

H2

SPressure,mm

Hg

EXP 100F

EST 100F

EXP 150F

EST 150F

EXP 200F

EST 200F

EXP 250F

EST 250F

Figure 8a. H2S partial pressure of DEA-H2S-H2O (DEA mass fraction = 0.25),experimental data from Lawson and Garst (1976)[15].


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0.1

1

10

1 10

m_H2S, mol/kg

H2SPressure,M

Pa

EXP 313.15KEST 313.15KEXP 333.15KEST 333.15KEXP 373.15KEST 373.15KEXP 393.15KEST 393.15KEXP 413.15KEST 413.15K

Figure 8b. H2S Partial Pressure of MDEA-H2S-H2O (MDEA molality = 4),experimental data from Kuranov et al. (1996)[11]


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16 4 Reactions

4 Reactions

DEA is a secondary ethanolamine, as shown in Figure 9. It can associate withH+to form an ion DEAH+, and can also react with CO2to form a carbamateion DEACOO-.

Figure 9. DEA Molecular Structure

MDEA is a tertiary ethanolamine, as shown below in Figure 10. It canassociate with H+to form MDEAH+but can not react with CO2to producecarbamate as is the case for primary or secondary ethanolamines.

Figure 10. MDEA Molecular Structure

The electrolyte solution chemistry has been modeled in Aspen Properties (seeDEA+MDEA Properties.aprbkp) using the CHEMISTRY model DEAMDEA.Chemical equilibrium is assumed with all the ionic reactions in the CHEMISTRYDEAMDEA. Since the kinetics of CO2 absorption play an important role indetermining the extent of CO2 capture in the absorber, the assumption ofchemical equilibrium made in the Chemistry model is insufficient. A ReactionSet called RDEAMDEA has been created in HYSYS to accurately model thekinetics. In RDEAMDEA, all reactions are assumed to be in chemicalequilibrium except those of CO2with OH

-, CO2with DEA and CO2with MDEA.

A. Chemistry : DEAMDEA (Configured in Aspen Properties)

1 Equilibrium OHOHO2H 32


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4 Reactions 17

2 Equilibrium 3322 HCOOHO2HCO

3 Equilibrium 23323 COOHOHHCO

4 Equilibrium OHDEAOHDEAH 32

5 Equilibrium

32 HCODEAOHDEACOO 6 Equilibrium OHHSSHOH 322

7 Equilibrium OHSHSOH 32

2

8 Equilibrium OHMDEAOHMDEAH 32

B. Reaction ID: RDEAMDEA (Configured in Aspen HYSYS)

R1 Equilibrium OHDEAOHDEAH 32

R2 Equilibrium OHOHO2H 32

R3 Equilibrium OHCOOHHCO 32323

R4 Equilibrium OHMDEAOHMDEAH 32

R5 Equilibrium OHHSSHOH 322

R6 Equilibrium OHSHSOH 32

2

R7 Kinetic 32 HCOOHCO

R8 Kinetic OHCOHCO 23

R9 Kinetic OHDEACOOOHCODEA 3-

22

R10 Kinetic 223- COOHDEAOHDEACOO

R11 Kinetic -322 HCOMDEAHOHCOMDEA

R12 Kinetic OHCOMDEAHCOMDEAH 22-

3

The equilibrium expressions for the reactions are taken from the work ofAustgen et al. (1988, 1991)[29,30]and Jou et al. (1982, 1993)[8,9, 10]. Thepower law expressions (T0not specified) are used for the rate-controlledreactions (reactions R7-R12 in RDEAMDEA):

N

i

a

i

n iC)RT

E(kTr

1

exp (1)

Where:

r= Rate of reaction;

k= Pre-exponential factor;

T= Absolute temperature;

n= Temperature exponent;


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18 4 Reactions

E= Activation energy;

R= Universal gas constant;

N= Number of components in the reaction;

Ci= Concentration of component i;

ai= The stoichiometric coefficient of component iin the reaction equation.In equation (1), the concentration basis is Molarity, the factor n is zero, k and Eare given in Table 2.

Zhang (2002)[31]assumed that free DEA can transfer CO2to MDEA andregenerate by itself simultaneously:

(A)22 CODEACODEA

(B) DEACOMDEAMDEACODEA 22

(C) -322 HCOMDEAHOHCOMDEA

We combine these three reactions and obtain the following reaction:(D) -

322 HCOMDEAHOHCOMDEA

Reaction (D) is used to represent the chemical equilibrium between MDEA andCO2, and the following rate expression is used to represent the catalytic effectof DEA on reaction (D):

2exp CODEAMDEA

n CC)CRT

E(kTr (2)

To implement the catalytic effect of DEA on reaction (D), we set thestoichiometric coefficient of DEA to 0 and the concentration exponent of DEAto 1 when we edit reactions R11 and R12 (Figure 11).

Figure 11a. Specifications of Reaction 11


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4 Reactions 19

Figure 11b. Specifications of Reaction 12

The kinetic parameters for reactions R7, R9 and R11 in Table 2 are derivedfrom the work of Rinker et al. (1996)[3],Pinsent et al. (1956)[4], andRamachandran et al. (2006)[5]. The kinetic parameters for the correspondingreversible reactions R8, R10 and R12 are calculated by using the kineticparameters and the equilibrium constants of the forward reactions R7, R9 andR11.

Table 2. Parameters k and Ein Equation (1)

Reaction k E, cal/mol

R7 4.32e+13 13249

R8 2.38e+17 29451

R9 6.48e+6 5072

R10 1.34e+17 11497

R11 3.12e+8 7432

R12 1.26e+12 15334


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20 5 Simulation Approach

5 Simulation Approach

The HYSYS flowsheet used to model the removal of CO2 using DEA andMDEA is shown below:

Figure 12. Rate-Based DEA+MDEA Simulation Flowsheet in Aspen HYSYS

The actual field performance data for an operating column from Weiland(2001)[1]were used to specify feed conditions and specifications for theabsorber.


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5 Simulation Approach 21

Unit Operations- Major unit operations used in this flowsheet are describedin Table 3

Table 3. HYSYS Unit Operation Blocks Used in the Rate-Based DEA+MDEA Model

Unit Operation HYSYS Block Comments / Specifications

ABSORB

ER

RateBased Column Purpose: Models amine/sour gas contactor/absorber

1. Calculation type: Rate-Based

2. 22 Stages

3. Top Pressure: 900psig

4. Reaction condition factor: 0.5

5. Film discretization ratio: 2

6. Heater Cooler: Heat loss is ignored for the absorber

7. Reaction: Reaction ID is RDEAMDEA for all stages

8. Tray Type: Sieve

9. Tray Diameter: 5ft

10 Sieve hole area to active area fraction: 0.0811. Mass transfer coefficient method: Chan and fair (1984)

12. Interfacial area method: Zuiderweg (1982)

13. Interfacial area factor: 1

14. Heat transfer coefficient method: Chilton and Colburn

15. Holdup correlation: Bennett et al. (1983)

16. Film resistance: Discrxn for liquid film; Film for vaporfilm

17. Additional discretization points for liquid film: 5

18. Flow model: Mixed

19. Estimates: provide temperature estimates for all stages.

These estimates are intended to aid convergenceNote:

1. The ABSORBER RateBased Column uses the Truesimulation approach because the reaction rateexpression requires the composition of individual ions.

2. A True to Apparent transition is used to compute theapparent composition of the RICH AMINE stream toensure consistent calculations in the downstream blocks

VLV-100 Valve Purpose : Reduces RICH AMINE pressure to 90 psi

FLASH TK Separator Flash Tank

L/R HX Heat Exchanger Purpose: Lean/Rich heat exchanger

Tube-side outlet temperature:200F

REGENERATOR RateBased Column Purpose: Models the stripper/regenerator

1. Calculation type: Equilibrium

2. 20 Stages including Condenser and Reboiler

3. Top Pressure: 21 psi


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22 5 Simulation Approach

Unit Operation HYSYS Block Comments / Specifications

4. Distillate Mass Flow Rate : 5000 lb/hr

5. Mass Reflux Ratio : 1

Note:

1. The REGENERATOR RateBased Column uses the True

simulation approach because the reaction rateexpression requires the composition of individual ions.

2. A True to Apparent transition is used to compute theapparent composition of the REGEN BTTMSstream toensure consistent calculations in the downstream blocks

TANK Mixer Purpose : Models tank holding DEA+MDEA solution

Computes MAKEUP H2O flow from specified recirculation rate

COOLER Cooler Purpose : Cools lean amine solution to 118F

P-100 Pump Purpose : Raises pressure of lean amine to 900 psig


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5 Simulation Approach 23

Streams- Feeds to the absorber are SOUR GAS containing N2, CH4, C2H6,C3H8, n-C4H10, i-C4H10, n-C5H12and CO2and AMINE TO CONTACTORcontaining aqueous DEA and MDEA solution loaded with some CO2. Feedconditions are summarized in Table 4.

Table 4. Feed specificationsStream ID SOUR GAS AMINE TO CONTACTOR

Temperature: F 80 118

Pressure: psig 910 910

Total flow 106351.7 lb/hr 7.548e4 lb/hr

Composition Mole-Frac Mass-Frac

H2O 0 0.564

CO2 0.0199 0.006

DEA 0 0.15

MDEA 0 0.28

CH4 0.8544 0C2H6 0.066 0

C3H8 0.0236 0

C4H10-01 0.0077 0

C4H10-02 0.0089 0

C5H12-01 0.017 0

N2 0.0019 0


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24 6 Simulation Results

6 Simulation Results

The simulation was performed using Aspen HYSYS V7.3. Key simulationresults are presented in Table 5.

Table 5. Key Simulation Results

CO2mole fraction in SWEET GAS 1082 ppmLoading of Rich Amine, Moles Acid Gas/Moles Amine 0.3902

Loading of Lean Amine, Moles Acid Gas/Moles Amine 0.036


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References 25

References

[1] R.H. Weiland, J.C. Dingman,Eliminating Guess Work,HydrocarbonEngineering, 2001

[2] Aspen Technology Inc., 2007

[3] E.B. Rinker, S.S. Ashour, O.C. Sandall,Kinetics and Modeling of CarbonDioxide Absorption into Aqueous Solutions of Diethanolamine, Ind. Eng.Chem. Res., 35, 1107-1114 (1996)

[4] B.R. Pinsent, L. Pearson, F.J.W. Roughton, The Kinetics of Combination ofCarbon Dioxide with Hydroxide Ions, Trans. Faraday Soc., 52, 1512-1520(1956)

[5] N. Ramachandran, A. Aboudheir, R. Idem, P. Tontiwachwuthikul,Kineticsof the Absorption of CO2into Mixed Aqueous Loaded Solutions ofMonoethanolamine and Methyldiethanolamine, Ind. Eng. Chem. Res., 45,2608-2616(2006)

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co2 capture using dea+mdea

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