che 414 chemical engineering laboratory ii
DESCRIPTION
ChE 414 Chemical Engineering Laboratory II. Instructor Dr. C. Niu. September, 2006. Website: http://www.engr.usask.ca/classes/CHE/414/index.html Text : ChE 414.2 Laboratory Manual (available online at course website) Office hours: Thurs & Fri 10:00 a.m. – 11:00 a.m. - PowerPoint PPT PresentationTRANSCRIPT
ChE 414Chemical Engineering Laboratory II
September, 2006
Instructor
Dr. C. Niu
Website: http://www.engr.usask.ca/classes/CHE/414/index.html
Text: ChE 414.2 Laboratory Manual (available online at course website)
Office hours: Thurs & Fri 10:00 a.m. – 11:00 a.m. Rm: 1C129 Eng. Bld.
What Labs ?
• Surge Tank Data Acquisition and Process Dynamics
• Fermentation: Kinetics of Yeast Growth• Packed Column: Pressure Drop and
Flooding• Filtration• Centrifugal Pump
What Courses related?
Surge Tank: CHE 413, 423 (process dynamics and control);
CHE 210, 320 (fluid mechanics)
Fermentation: CHE 461 (biochemical engineering)
Packed column: CHE 315, 421 (mass transfer)
Filtration: CHE 315, 421 (mass transfer); CHE 210, 320 (fluid mechanics)
Centrifugal Pump: CHE 210, 320 (fluid mechanics)
COURSE OBJECTIVES:
Develop skills in - Equipment operation
- Data recording
- Analysis of the data using academic theory
- Technical report writing
in the selected typical Chem. Eng. processes
Marking
• Lab performance: (4X2.5%)• Lab notebook: 10%• Technical letters: (2X10%)• Brief report: 25%• Formal report: 35% Overall mark: 100%
No exam
Plagiarism is DEFINITELY NOT acceptable!– Copy other people’s report– Citing without referencing the source
Plagiarism results in 0 mark for the report
Be aware of & Follow the new University of Saskatchewan Academic Honesty/Dishonesty definitions, rules and procedures
www.usask.ca/honesty.
Due Date and Overdue Penalty
• Due date– 2 weeks after the experiment date.
10 “free” late hand-in days for the whole course Indicate on your report when use it.
• Penalty– 10% of the full marks (100) per week (2%/day)
deducted from the late reports– submissions will NOT be accepted after
Dec. 18th, 2006.
Requirements
• Lab performance
• Write-ups: technical writing
• Fundamentals of each lab
Lab performance
Be prepared for:• Objectives• Theory / knowledge• Design of experiment• Parameters to be measured• Apparatuses, procedures and principles • Find out: what to learn
Initiate the contact for the pre-lab helpwith the demonstrators & the lab coordinator
Lab performance
• Follow the experimental procedures• Record observations in Lab Notebook• Test the validity of data and/or results • Pay attention to SAFETY issues
– personnel– equipment
During the experiments:
Write-ups / Reports
• Technical memo• Brief report• Formal report
• Lab notebook: during the experiments
Write-ups / Reports
One student is required to hand in– 2 technical letters– 1 brief report– 1 formal report– 1 lab notebook
Write-ups / Reports
No repetition in each group for
– formal report– brief report– technical letters
Write-ups / Reports
You Your partner
Tech. letters Labs A and B Labs C and D
Brief report Lab C Lab A
Formal report Lab D Lab B
Lab notebook Labs A,B,C,D Labs A,B,C,D
In one group, you may label the 4 labs by A, B, C, and D in your own order. Each member of the group should keep the same order.
Lab NotebookNo sheets of paper
Permanently bounded & recorded
• Briefly outline the title, apparatus, experimental conditions and procedures before labs
Suggest making table for recording data
• Record clearly all original observations& simple calculations of data
• MUST be examined, dated and initialed by the TAs before leaving the laboratory
Refer to ChE 333 class website for
RULES FOR LABORTORY NOTEBOOKS
Submit the lab notebook at the end of the term for marking
Lab Notebook
Technical Memorandum• Body of text: maximum two pages • Introduction
- concise introduction of the system used- a brief statement of the objectives of the experiment- a general description of the procedure followed
• Results- discussions and comparison of all required results with values from literature- equations used- a brief table of results or major graphs attached to support the conclusions.
• Conclusions and recommendations
• Sign your memo on the last page below the text
To:From: (your name, group X)Re: (Lab name)Date: (of the preparation of the memo)
Your group logo(optional)
The text of memo is put here below the line.
ChE 414 - TECHNICAL MEMORANDUM GRADE SHEETStudent: ______________________________________Experiment: ______________________________________
Due Date: ___/___/___ Date Rec’d: ___/___/___ Late Penalty: ___ %
MAX MARKPRESENTATION (FORMAT) 3
READABILITY 3TECHNICAL CONTENT(RESULTS & CONCL.)
4
Total 10
Formal Technical Report– Title page and Table of Contents– Abstract– Table of contents, table of figures, table of tables– Introduction– Review of theory or literature– Experimental Section: apparatus and procedure– Results and Discussion– Conclusions– Recommendations– Nomenclature– Reference– Appendices
Formal Technical Report
Title page• Course number• Name (Your name and state the partner’s name)• Lab title• Prepared for (instructor’s name)• Date lab done• Date report due
Table of contents
Formal Technical Report
Abstract• State briefly the purpose of the investigation• Describe briefly how the results are obtained• Give all required results in a concise and
quantitative format if possible.• Use words, no tables, figures and equations• Normally no more than 250 words.
Formal Technical Report
Introduction• Include information on the subject of the
investigation and its importance in industry
• Cite the references;
• Describe clearly the objectives of the lab.
Formal Technical Report
Literature review or theory• Provide sufficient theoretical background
to the particular experiments• Develop the equations or models to correlate
your experimental data.detailed derivation placed in Appendix
• Describe how to obtain the model parameters and predict the particular system
• Cite the references
Formal Technical ReportApparatus and Experimental Procedures
• Specify the main apparatuses used make, model and use
• Describe the procedures Highlight important experimental conditions
• Give the names of quality of the materials.
Make sure other people can repeat your work and obtain the same results if they follow your description.
Formal Technical ReportResults and Discussions
• Present the significant experiment results required in the Lab Manual in words and graphs.
• State the data treatment processes and the outcomes.
• Discuss the results of experiments and model simulations or predictions.
• Compare your results with that in literatures if available.
• Logically discuss and lead to conclusions.
Attention• Consistent format
• The unit for every parameters in the equations has to be conformed.
• Figures or Tables in the body of text– Titles of figures, axes, and tables
– Briefly state the experimental conditions
– Experimental data: represented by unique symbol for each group of data in figures
– Modeling curves: different lines with legends– Show model significance when fitting models
Modeling the effect of IS on Cr uptakes
40±1 mg AWUS, 20±0.2 mL solution
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0 2 4 6 8 10Equilibrium Cr concentration (mM)
Cr u
ptak
e (m
mol
/g)
without NaCladdition
0.1M NaCl
0.1M NaCl
model predicting curve model prediction when =1
pH 2.0
relative dev.: 5.1%
relative dev.: 11.5%
error bar: 95% confidence interval
Formal Technical Report
Conclusions and Recommendations
• Conclusions should be summarized following the discussions.
• Lists your suggestions on how we can improve the labs.
Formal Technical Report
Nomenclature• Completely lists the symbols that appear
in your report, their definition and unit in a professional and consistent format.
Refer to a published paper.
Formal Technical Report
Reference
• Completely lists every reference cited, mentioned or used in the text of the report in a professional and consistent format.
• Follows either the number order or the alphabetical order.
Formal Technical ReportReference format examples
In the text:……Adams concluded that ……1. However, that conclusion may be suspicious because ……2
In the Reference section:
References1. Adams, A. B. title of publication. ……2. Cook, H. M., Author #2, ……
Ref: Industrial and Engineering Chemistry Research
or in the text:It was concluded ( Adams, 2001) that ……. However, that conclusion may be suspicious (Davis and Volesky, 2001) because ……(Niu, et. al., 2005)
ReferencesAdams, A. B. year, title of publication, publisher, page (book)Davis, T. and B. Volesky, year, title of paper, volume, issue, pages (paper)Niu, C., M. Huang and M.Volesky, year ….
Ref: Canadian Journal of Chemical Engineering
Formal Technical Report
Appendices• Raw data (neat with tables)• Calculated data• Sample calculation (using a set of data to
show the steps of calculations) • Tables and Figures
Brief Technical Report– Title page and Table of contents – Summary
a brief introduction stating the nature and purpose of the investigation a brief explanation of the procedures and apparatuses a summary of all the required results
– Results and Discussion: include major graphs or tables– Conclusions– Recommendations– Appendices: only raw experimental data and a sample
calculation
Absence of abstract, introduction, theory/literature review, materials and methods sections
A good report• Careful measurements• Correct calculations• Understanding and use of the
theory or models• Logical discussions• Correct conclusions
OrganizedClarityNo grammar & typographical errors
• References
Fundamentals of labs
FiltrationA Standard Unit Operation:
physical separation of solid particles from liquid or gas.a porous medium: fluid to pass through
solid particles to be retained.
Slurry flow Filtrate
Filter mediumFilter cake
a filtration plant for Water Treatment System
(http://www.carrolltown.pa.us/CBMA/)
Filtration Theory• The driving force of filtration separation:
the pressure upstream of the filter
Slurry flow Filtrate
Filter medium
Filter cake
L
FiltrationObjectives:
- Determine the relationship between the upstream filter pressure and the flowrate
- Evaluate the applicability of the selected model
- Determine the model parameters
- Demonstrate the effect of filter aid (perlite) on the filtration of CaCO3 slurry
- Develop skills on design of a filtration process
Theory:
The upstream filter pressure P (Pa)(Bennett and Myers, 1982)
P=(K1V+K2)Qif the cake is incompressible
For constant flowrate filtration Q,V=Qt, thenP=K1Q2t+K2Q Plot P~t, get K1 and K2
where V: the volume of filtrate collected (m3) Q: the flowrate of filtrate (m3/s);t: time(s);K1 and K2 : constants, highly dependent on the characteristics of cake and filter medium, respectively
K1 and K2 values:
• Dependent on the characteristics of cake, liquid and filter medium
• Determined by measuring the upstream filter pressure P as a function of time at specific Q
• Evaluate the resistances of the cakeand filter medium
• for filter design: theoretically predict the required driving force
Fermentation: Kinetics of Yeast Growth
• Involves in Yeast growth on substrate glucose
• Major end products: Ethanol: beer, wine, fuel yeast biomass: high poundage product
500million pounds/year
Yeast needed for daily life
Fermentation: Kinetics of Yeast Growth
Objectives:- Demonstrate the yeast batch growth curve- Determine the parameters of Monod equation.- Calculate the yields of the products- Design a fermentor for ethanol production
Fermentation theory
(J.M. Lee, 1992)
C6H12O6 → 2C2H5OH + 2CO2
• Substrate: glucose • Microorganism: yeast• Low oxygen concentration• theoretical yielded ethanol: 51.1% by
weight
Typical growth curve for microorganism cells
Theory cont.
(1/hr) ismmicroorgan theof rategrowth specific theis
1
Then, (h). timeis t g/L,ion concentrat cell theis X
is lab in this systembatch ain biomassyeast theof production The
dtdX
X
XdtdX
growth
.determined is t, versusX measureally experiment
ln
Therefore,. ,when
g/L, 1 than lessusually (g/L),constant saturation is );(h biomass of rategrowth specificmaximun theis
(g/L)ion concentrat (glucose) substrate theis S where
:equation Monod toaccording modeledoften is
0
mS
S
1-m
m
m
m
S
tXX
KSK
SKS
Theory cont.
Theory cont.
(g/L).ion concentrat enthanolproduct end theis P
consumed substrate ofamount the to producedproduct theof ratio the: yield ethanol-
consumed substrate ofamount the to produced biomass theof ratio the: yield biomass -
dtdSY
dtdP
YdtdSY
dtdX
Y
PS
PS
XS
XS
Theory cont.
.determined are and , versus , measureally Experiment
ly.respective biomass, and substrate ofion concentrat inital theare 0
and 0
)0
(
)
0(
)0
(
:becomes equations above theconstant, is yield When the
PSY
XSYSPX
XS
SS
PPS
Y
SS
XX
XSY
Surge Tank Data Acquisition and Process Dynamics
• Common problem: propagation of disturbances between processes • Solution : surge tank
– Damp out the changes of the inlet flowrate– Deliver a steadier outlet flowrate to the downstream process
(http://www.ih.navy.mil/cbf/images/SurgeTank)
Surge Tank Data Acquisition and Process Dynamics
Objectives:- Evaluate the applicability of selected models relating the outlet flowrate versus head - Derive and test mathematical models for the transient behavior of a liquid surge tank- Record the data with automatic acquisition system - LabVIEW
Surge Tank
• Data acquisition and control: a computer with LABVIEW Software package
Automation, more precise.
• Collect data: water flow rate and water head in the tank
Familiar with the software
qout qin
h
A
Surge Tank
h: the height of the liquid level in the surge tank (head) (ft);qin: the inlet water flowrate (ft3/s);qout: the outlet water flowrate (ft3/s)A: the cross sectional area (ft2).
Surge Tank Theory
Mass balance at transient period:
Aoutqinqdtdh
/)(
t: time (s), where the density of the liquid is constant
Theory cont.• Flow exit a surge tank through a valve follows:
(D. R. Coughanowr and L. B. Koppel, 1965, p.60)
qout ~ h½
e. g. qout = C1h½ (qout is linearly proportional to h½ )qout = Co+C1h½ or qout = Co+C1h½ + C2 (h½)2 + C3 (h½)3 +…+ Cn (h½)n (n> 1, qout is non-linearly proportional to h½ )
• Constant Ci is determined by fitting the above equations, respectively, to the experimental data (qout ~ h1/2) at steady state, where qout = qin. (Microsoft Excel)
• Compare the fitting results of different models
Theory cont.
Aoutqinqdtdh
/)(
Substituting the qout in the mass balance equation yields non-linear differential equation:
Solutions:-Analytical:
closed-form, a general picture of the process behaviorindependently of the particular values of the input variablesprocess design and control limited to linear processes
-Numerical:dependent on the values of the input variables.
Analytical Solution• Linearize the non-linear differential equation by Taylor series expansion of the non linear term around a point
(e.q. steady state) (Stephanopoulos, G., 1985, p.116-121)
• Convert the differential equation to algebraic equation by Laplace transforming(D. R. Coughanowr and L. B. Koppel, 1965, p.13-41, 67-70)
• Invert the transform to get h as a function of time(D. R. Coughanowr and L. B. Koppel, 1965, p.13-41)
Use this equation to describe the experimental data at unsteady state
Analytical Solution• For example, qout = C1h½ ,
• Linearize the non-linear differential equation:(Stephanopoulos, G., 1985, p.116-121)
AhCqdtdh
in /)( 2/11
Subscript s represents the steady state.121
2
)(1
,
CshR
shhRsoutqoutq
Linear form
)(,, ' shhsoutqsoutqoutq
Take the first order of Taylor series expansion of the term qout
around a point (e.q. steady state):
Analytical SolutionSubstitute the first order Taylor series expansion of qout in
the differential equation,
AR
hhqqdtdh s
soutin /)( ,
soutqsinq ,, state,steady at
ARHQ
dtdH
qqQhh
AR
hhqqdtdh
in
sininins
ssinin
/)(
obtain
,,Hvaribles,deviation use
/)(
,
,
Analytical Solution
Convert the differential equation to algebraic equation by Laplace transforming(D. R. Coughanowr and L. B. Koppel, 1965, p.13-41, 67-70)
RA
sR
sinQ
sH
1)(
)(
)(sH)(sQin
is Laplace transform of derivation variable h-hs
is Laplace transform of derivation variable qin-qin,s
s represents the Laplace function.
Analytical SolutionWhen the inlet flowrate is increased or decreased around certain
steady state:
MsinqinqinQ
0
,
t<0
t≥0
Take the transform of Qin
sM
sinQ0
)(t<0
t≥0
Input the time conditions,
)(sH
)1(
0
ssRM
=
t<0
t≥0
Invert the transform,(D. R. Coughanowr and L. B. Koppel, 1965, p.13-41)
)1( t
eRMshhH
t ≥ 0
)1( t
eRMshh
Numerical Solution
Eularian theory: (Rice, RG, 1995)
)(/)( hfAoutqinqdtdh
)1(*1 nhftnhnh
Compare the analytical model solution with the numerical solution. Use two equations of qout ~h1/2 at n=1 & n>1 for all cases in this lab.
Where qout = Co+C1h½ + C2 (h½)2 + C3 (h½)3 +…+ Cn (h½)n
n = 1, …n
Packed Column: Pressure Drop and Flooding
Packed column: widely-used industrial equipment for mass transfer processes: distillation, adsorption and extraction
(http://www.syndel.com/images/powell_apr02-2.jpg)
Packed Column
Gas-liquid counter-current flow in packed column:
• Liquid: downwards flow• Gas: upwards flow• Flooding conditions
L in
L out
G in
G out
Design Criteria
• pressure drop: caused by the resistance of packing to fluid flow.
• The flood velocity: an important parameter for gas-liquid packed column design
Packed Column: Pressure Drop and Flooding
Objectives:- Determine the relationship of pressure drop and the flowrate in a packed column
- Evaluate the applicability of Ergun equation for a single gas flow system- To determine the pressure drop and flooding condition in a gas-liquid system
Packed ColumnPressure drop for a single flow through packed bed-Ergun equation
(Treybal, R.E., 1980, P.200.)
;/ftlbin density gas is
h./ftlbin velocity mass lsuperficia is
ft;in bed packed down thelength is number; Renold theis Re
ft;in packing ofdiameter effectiveor diameter is
;lbft/hlb104.17lbft/s32.174lb
volume;bed l void/totaof volumeporosity is ;lb/ftin pressure is
where
75.1Re
)1(150)1(
3m
2m
f2
m8
f2
m
2
2
3
g
c
ρ
G
z
d
g
P
Gdg
zP
p
gpc
Packed Column TheoryFlooding conditions
for a gas-liquid flow through packed bed (B. Miline, 1994)
bYaYeZp
Y: a function of gas flowratea, b, e: constants for a specific system.
Symbol definition! Units!
Packed Column
• Models are empirical equations.
• Different models fit differential systems.
• Evaluate the applicability of the selected model for the experiment system
Centrifugal Pump
• The most common type of fluid mover in the chemical industry
• To convert energy of a prime mover (an electric motor or turbine) first into velocity or kinetic energy and then into pressure energy of a fluid that is being pumped.
http://www.pumpworld.com/centrif1.htm
Centrifugal Pump
- To determine the characteristics of a centrifugal pump including total head, brake horse power, efficiency and net positive suction power (NPSH) versus flowrate.
- To determine the size of a geometrically similar pump needed to pump against a total head of 100 feet of water at peak efficiency
Reference BooksC.O. Bennett & J.E. Myers, "Momentum, Heat, and Mass
Transfer", 3rd Edition, McGraw-Hill, 1982.D.R. Coughanowr & L.B. Koppel, "Process Systems
Analysis and Control", McGraw-Hill, 1965.G. Stephanopoulos, “Chemical Process Control –
Introduction to Theory Practice”, Prentice Hall, 1984.J.M. Lee, "Biochemical Engineering", Prentice Hall, 1992,
pp 100-152.R.E. Treybal, "Mass-Transfer Operations", McGraw-Hill,
1980.R.S. Blicq. "Technically-Write!", Prentice Hall, 2nd Edition,
1981.R.G. Rice, “Applied Mathematics and modeling for
chemical engineers”, John Wiley and Sons, Inc. 1995, pp231.
Other References1. James R. Welty, Charles E. Wicks, Robert E. Wilson, and Gregory
Rorrer, Fundamentals of Momentum, Heat and Mass Transfer. 4th Edition, John Wiley and Sons, Inc. 2001
2. Jaime Benitez, Principles and Modern Applications of Mass Transfer Operations. John Wiley and Sons, Inc. 2002
3. Donald R. Coughanowr, Process Systems Analysis and Control. McGraw-Hill, Inc. 1991
4. Hans, F. Ebel, Claus Bliefert, and William E. Russey, The Art of Scientific Writing. 2nd Edition, John Wiley and Sons, Inc. 2004
5. Christie J. Geankoplis, Transport Processes and Separation Process Principles. 4th Edition, Prentise-Hall, Inc. 2003
6. Milne, W.E., Numerical Solution of Differential Equations, Wiley, NY, 1953.
7. Quinney, D., Introduction to the numerical solution of differential equations, research Studies Press, NY, 1987.
Have your own references to make your report strong!
Important dates
• 19 Sep: Last day to change first term registration.
• 9 Oct: Thanksgiving (University Closed), • 4 Dec: Last day of classes.• 18 Dec: Last day to hand in laboratory
reports and laboratory notebooks for marking
Summary• Academic theory understanding• Lab performance• WRITEUPS
Successful!