Continuous Stirrer Tank Reactors in Series

Mini Project Cstrs in seriesMini Project Cstrs in series

Dpeartment of Chemical Engineering Dpeartment of Chemical Engineering

NWFP UET PESHAWAR NWFP UET PESHAWAR

PakistanPakistan


Group MembersGroup Members

Muhammad AzeemMuhammad Azeem

Muhammad ShakirMuhammad Shakir

Qazi Muhammad AliQazi Muhammad Ali

Sami UllahSami Ullah

Mehfooz Ur RehmanMehfooz Ur Rehman

Jehangir KhanJehangir Khan


Supervisor:Supervisor:

Engr. Ihsan ullahEngr. Ihsan ullah


Mini ProjectMini Project

Continuous stirrer tank reactors Continuous stirrer tank reactors in in series.series.


Summary of previous work.Summary of previous work.

1.1. IntroductionIntroduction

2.2. CommissioningCommissioning

3.3. Calibration of pumpsCalibration of pumps


Results of calibration of pumps.Results of calibration of pumps.

Pumps calibration.

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Time constant calculation for Time constant calculation for different flow rates.different flow rates.

For liquid level system time constant is given For liquid level system time constant is given byby

T = V/qT = V/q

Where V is the operating volume of tankWhere V is the operating volume of tank

And q is flow rate.And q is flow rate.


Determining the operating volume Determining the operating volume of one tank.of one tank.

Fill the first two tanks until the second tank Fill the first two tanks until the second tank overflows.overflows.Open the drain valve and collect all liquid in a Open the drain valve and collect all liquid in a graduated beaker.graduated beaker.Divide this volume by 2 to get the operating Divide this volume by 2 to get the operating volume of single tank.volume of single tank.ResultsResultsTotal volume = 1350mlTotal volume = 1350mlthus V1 = 1350ml/2 = 675mlthus V1 = 1350ml/2 = 675ml

Now T can be found by our adjusted flow rate.Now T can be found by our adjusted flow rate.


Experimental work to be performed. Experimental work to be performed.

Section 1:Section 1:

Dynamics of stirred tank.Dynamics of stirred tank.


Chemical reaction in stirred tank reactors Chemical reaction in stirred tank reactors in seriesin series


Dynamics…Dynamics…

The way how the system responds when The way how the system responds when any type of changes in its input are any type of changes in its input are introduced is known as its dynamic introduced is known as its dynamic behavior. behavior.


Experiments performed on CSTRsExperiments performed on CSTRs


Effect of step input change.Effect of step input change.Response of tank concentration to an impulse Response of tank concentration to an impulse Change.Change.Influence of flow rate on a three tank system Influence of flow rate on a three tank system following a step change in input concentration.following a step change in input concentration.Response to step change in input concentration Response to step change in input concentration of system comprising on one stirred vessel and of system comprising on one stirred vessel and dead time module.dead time module.


Time constantTime constant

The value of Y(t) reaches 63.2 percent of its ultimate value when the time elapsed is equal to one time constant T. When the time elapsed is 2T,3T, and 4T, the percent response is 86.5, 95, and 98, respectively. From these facts, one can consider the response essentially completed in three to four time constants.


Experiment no 1:Experiment no 1:Effect of a step input change.Effect of a step input change.

Procedure:Procedure:1.1. Make up 5 litres of 0.1M potassium chloride solution.Make up 5 litres of 0.1M potassium chloride solution.

Formula of potassium chloride = KClFormula of potassium chloride = KClMolecular weight of potassium ,K= 39gmMolecular weight of potassium ,K= 39gmMolecular weight of Chlorine, Cl= 35.5gmMolecular weight of Chlorine, Cl= 35.5gmMolecular weight of KCl = (39+35.5)gmMolecular weight of KCl = (39+35.5)gm

Molecular weight of KCl = 74.5gmMolecular weight of KCl = 74.5gmFor .1M KCl solutionFor .1M KCl solutionas KCl is in solid formas KCl is in solid form.1M KCl solution = Molarity *Molecular weight of KCl .1M KCl solution = Molarity *Molecular weight of KCl

= .1*74.5gm = 7.45gm (for 1litre solution)= .1*74.5gm = 7.45gm (for 1litre solution)For 5 litre solution;For 5 litre solution;

5 litres of 0.1M KCl solution = 5lit * 7.45gm = 37.25gm KCl5 litres of 0.1M KCl solution = 5lit * 7.45gm = 37.25gm KCl


ProcedureProcedure1.1. Dissolve 37.25gm of KCl in 5litre water to make.1M KCl solution.Dissolve 37.25gm of KCl in 5litre water to make.1M KCl solution.2.2. Fill one of the reagent feed vessel with this solution.Fill one of the reagent feed vessel with this solution.3.3. Half fill the other feed vessel with demineralised or deionised water.Half fill the other feed vessel with demineralised or deionised water.4.4. Pour this water into each of the reactors until they are full to standpipe Pour this water into each of the reactors until they are full to standpipe

overflow levels. This is to save time as it would take several minutes to fill overflow levels. This is to save time as it would take several minutes to fill the reactors using the feed pumps.the reactors using the feed pumps.

5.5. Start the water feed pump and set to 6.0 on speed adjust dial.Start the water feed pump and set to 6.0 on speed adjust dial.6.6. Start the stirrers and set to 8.0 on speed adjust dial.Start the stirrers and set to 8.0 on speed adjust dial.7.7. Start taking conductivity reading after every 30sec for period of 45minStart taking conductivity reading after every 30sec for period of 45min8.8. After few minutes, when water is flowing from the tank, through each After few minutes, when water is flowing from the tank, through each

reactor in turn and eventually out to drain. Stop the water feed pump and reactor in turn and eventually out to drain. Stop the water feed pump and immediately start the KCl pump with the speed set to 6.0 on the speed immediately start the KCl pump with the speed set to 6.0 on the speed adjust dial.adjust dial.

9.9. When experiment is complete, use Microsoft excel to plot graphs of When experiment is complete, use Microsoft excel to plot graphs of conductivity vs. time and explain their shape.conductivity vs. time and explain their shape.


Effect of step input change in tank 1,2 and 3 Effect of step input change in tank 1,2 and 3 respectively by using experimental data.respectively by using experimental data.

Effect of step input change in tank 2.

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Finding time constant from Finding time constant from experimental data.experimental data.

First method:First method:Potentiometer speed = 6Potentiometer speed = 6Corresponding flow rate = 54.1 ml/minCorresponding flow rate = 54.1 ml/minVolume of one tank = 675 mlVolume of one tank = 675 ml

since,since, Time constant = T = V/qTime constant = T = V/q Time constant = T = 675ml/54.1(ml/min)Time constant = T = 675ml/54.1(ml/min)

T = 12.5minT = 12.5min


Continued…..Continued…..

Graphical method:Graphical method:

In step response curve the time In step response curve the time constant is achieved when ordinate of graph constant is achieved when ordinate of graph

Y(t)/A = .632Y(t)/A = .632

Where,Where,

Y(t) = K (conductivity)Y(t) = K (conductivity)

And,And,

A = ultimate value of K = 11.5(.1M KCl)A = ultimate value of K = 11.5(.1M KCl)


Calculating T for each tank.Calculating T for each tank.Tank 1:Tank 1:

K(t) = .632 * 11.52K(t) = .632 * 11.52kktt = k = ks s +7.3+7.3 = .56 + 7.3 = 7.84mS= .56 + 7.3 = 7.84mS

Corresponding time from experimental data:Corresponding time from experimental data:TT1 1 = 15min= 15min

Tank 2:Tank 2:K(t) = .632 * 11.52K(t) = .632 * 11.52k2 = kk2 = ks s +7.3+7.3 = .5 + 7.3 = 7.8mS= .5 + 7.3 = 7.8mS

Corresponding time from experimental data:Corresponding time from experimental data:T2 = 32minT2 = 32min


Corresponding time from experimental data:Corresponding time from experimental data:T3 = 49minT3 = 49min


Experiment no 2:Experiment no 2: Response of tank concentration to an impulse Response of tank concentration to an impulse

Change.Change.Procedure:Procedure:

1.1. Make up 5 litres of 0.1M potassium chloride solution.Make up 5 litres of 0.1M potassium chloride solution.2.2. So we have to dissolve 37.25gm of KCl in 5litre water to 5 litres of .1M So we have to dissolve 37.25gm of KCl in 5litre water to 5 litres of .1M

KCl solution.KCl solution.3.3. Fill one of the reagent feed vessel with this solution.Fill one of the reagent feed vessel with this solution.4.4. Half fill the other feed vessel with demineralised or deionised water.Half fill the other feed vessel with demineralised or deionised water.5.5. Pour this water into each of the reactors until they are full to standpipe Pour this water into each of the reactors until they are full to standpipe

overflow levels. This is to save time as it would take several minutes to fill overflow levels. This is to save time as it would take several minutes to fill the reactors using the feed pumps.the reactors using the feed pumps.

6.6. Start the water feed pump and set to 8.0 on speed adjust dial.Start the water feed pump and set to 8.0 on speed adjust dial.7.7. Set 5.0 as the flow rate on the salt feed pump.Set 5.0 as the flow rate on the salt feed pump.8.8. Start the stirrers and set to 8.0 on speed adjust dial.Start the stirrers and set to 8.0 on speed adjust dial.9.9. Start taking conductivity reading after every 30sec for period of 60min.Start taking conductivity reading after every 30sec for period of 60min.10.10. An impulse change is applied by switching off the water feed pump and An impulse change is applied by switching off the water feed pump and

instantly switching on the salt solution feed pump.instantly switching on the salt solution feed pump.11.11. Allow the salt solution to be pumped into the first reactor for 15 minutes Allow the salt solution to be pumped into the first reactor for 15 minutes

then instantly switch back to water again.then instantly switch back to water again.12.12. When experiment is complete, use Microsoft excel to plot graphs of When experiment is complete, use Microsoft excel to plot graphs of

conductivity vs. time and explain their shape.conductivity vs. time and explain their shape.


Effect of impulse change in tank 1,2 and 3 Effect of impulse change in tank 1,2 and 3 respectively by using experimental data.respectively by using experimental data.

Effect of a impulse change in tank 1.

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Experiment no 3:Experiment no 3:Influence of flow rate on a three tank system Influence of flow rate on a three tank system

following a step change in input concentration.following a step change in input concentration.

Procedure:Procedure:1.1. Make up 5 litres of 0.1M potassium chloride solution.Make up 5 litres of 0.1M potassium chloride solution.2.2. So we have to dissolve 37.25gm of KCl in 5litre water to make 0.1M KCl solution.So we have to dissolve 37.25gm of KCl in 5litre water to make 0.1M KCl solution.3.3. Fill one of the reagent feed vessel with this solution.Fill one of the reagent feed vessel with this solution.4.4. Half fill the other feed vessel with demineralised or deionised water.Half fill the other feed vessel with demineralised or deionised water.5.5. Pour this water into each of the reactors until they are full to standpipe overflow levels. This is Pour this water into each of the reactors until they are full to standpipe overflow levels. This is

to save time as it would take several minutes to fill the reactors using the feed pumps.to save time as it would take several minutes to fill the reactors using the feed pumps.6.6. Start the water feed pump and set to 4.0 on speed adjust dial.Start the water feed pump and set to 4.0 on speed adjust dial.7.7. Start the stirrers and set to 8.0 on speed adjust dial.Start the stirrers and set to 8.0 on speed adjust dial.8.8. Start taking conductivity reading after every 30sec for period of 45minStart taking conductivity reading after every 30sec for period of 45min9.9. After few minutes, when water is flowing from the tank, through each reactor in turn and After few minutes, when water is flowing from the tank, through each reactor in turn and

eventually out to drain. Stop the water feed pump and immediately start the KCl pump with the eventually out to drain. Stop the water feed pump and immediately start the KCl pump with the speed set to 6.0 on the speed adjust dial.speed set to 6.0 on the speed adjust dial.

10.10. Repeat the experiment twice with a KCl flow rate set 6.0 and 8.0 on the speed adjust dial.Repeat the experiment twice with a KCl flow rate set 6.0 and 8.0 on the speed adjust dial.11.11. When experiment is complete, use Microsoft excel to plot graphs of conductivity vs. time and When experiment is complete, use Microsoft excel to plot graphs of conductivity vs. time and

explain their shape.explain their shape.12.12. Determine time constant and verify that they are inversely proportional to respective flow Determine time constant and verify that they are inversely proportional to respective flow

rates.rates.


Effect of step input change in tank 1,2 and 3 Effect of step input change in tank 1,2 and 3 respectively when KCl feed pump set on 4.0 on respectively when KCl feed pump set on 4.0 on speed adjust dial.speed adjust dial.

Effect of step change input in tank 1.

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Effect of a step input change in tank 2.

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T =19.2minT =19.2min





Y(t)/A = .632Y(t)/A = .632

Where,Where,


And,And,





Corresponding time from experimental data:Corresponding time from experimental data:TT1 1 = 39.5min= 39.5min


This response is not achieved in the process period.This response is not achieved in the process period.


This response is not achieved in the process period.This response is not achieved in the process period.


Effect of step input change in tank 1,2 and 3 Effect of step input change in tank 1,2 and 3 respectively when KCl feed pump set on 6.0 on respectively when KCl feed pump set on 6.0 on speed adjust dial.speed adjust dial.


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T = 12.5minT = 12.5min


Continued….Continued….



Y(t)/A = .632Y(t)/A = .632

Where,Where,


And,And,





Corresponding time from experimental data:Corresponding time from experimental data:TT1 1 = 15min= 15min


Corresponding time from experimental data:Corresponding time from experimental data:T2T2 = 32min= 32min


Corresponding time from experimental data:Corresponding time from experimental data:T3T3 = 49min= 49min


Effect of step input change in tank 1,2 and 3 Effect of step input change in tank 1,2 and 3 respectively when KCl feed pump set on 8.0 on respectively when KCl feed pump set on 8.0 on

speed adjust dial.speed adjust dial.

Effect a step input change in tank 1.

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T = 9.1minT = 9.1min





Y(t)/A = .632Y(t)/A = .632

Where,Where,


And,And,



Calculating T for each tank.Calculating T for each tank.

Tank 1:Tank 1:K(t) = .632 * 11.52K(t) = .632 * 11.52kktt = k = ks s +7.3+7.3 = .58 + 7.3 = 7.88mS= .58 + 7.3 = 7.88mS

Corresponding time from experimental data:Corresponding time from experimental data:TT1 1 = 13.5min= 13.5min


Corresponding time from experimental data:Corresponding time from experimental data:T2T2 = 27.5min= 27.5min


Corresponding time from experimental data:Corresponding time from experimental data:T3 = 39.5minT3 = 39.5min


Relation between flow rate and Relation between flow rate and time constant.time constant.

Flowrate vs Time Constant(T1)

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Experiment no 4:Experiment no 4:Response to step change in input concentration of system Response to step change in input concentration of system comprising on one stirred vessel and dead time module.comprising on one stirred vessel and dead time module.

Procedure:Procedure:

1.1. Prepare 5 litres of 0.1M and 0.01M KCl.Prepare 5 litres of 0.1M and 0.01M KCl.2.2. Fill tank no. 3 and the dead time coil up to the overflow level with 0.1M KCl Fill tank no. 3 and the dead time coil up to the overflow level with 0.1M KCl

solution.solution.3.3. Connect the feed pump discharge to the tank no. 3 inlet fitting.Connect the feed pump discharge to the tank no. 3 inlet fitting.4.4. Start the pump from the 0.1M feed tank and adjust the flow to position 8.0 on the Start the pump from the 0.1M feed tank and adjust the flow to position 8.0 on the

speed adjust dial.speed adjust dial.5.5. Switch on the agitators and adjust the speed the speed to position 5.0 on the Switch on the agitators and adjust the speed the speed to position 5.0 on the

speed adjust dial.speed adjust dial.6.6. Adjust the overflow height to give an operating level in tank no. 3 almost at the Adjust the overflow height to give an operating level in tank no. 3 almost at the

standpipe overflow height.standpipe overflow height.7.7. Start taking readings of conductivity after 30sec over a 45 minutes period.Start taking readings of conductivity after 30sec over a 45 minutes period.8.8. Stop the 0.1M feed pump and immediately start the 0.01M feed pump adjusted to Stop the 0.1M feed pump and immediately start the 0.01M feed pump adjusted to

same flow rate.same flow rate.9.9. Convert conductivity readings to concentration.Convert conductivity readings to concentration.10.10. Plot curves relating concentration level (conductivity) and time for tank no. 3 and Plot curves relating concentration level (conductivity) and time for tank no. 3 and

dead time coil.dead time coil.


Response to step change in input concentration of system Response to step change in input concentration of system comprising on one stirred vessel and dead time module comprising on one stirred vessel and dead time module

using experimental data.using experimental data.

Response to a step change in input concentration in tank 3.

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Second method:Second method:Graphical method:Graphical method:


Y(t)/A = .632Y(t)/A = .632Where,Where,

Y(t) = K (conductivity)Y(t) = K (conductivity)And,And,



Calculating T for tank 3.Calculating T for tank 3.

Tank 3:Tank 3:K(t) = -.632 * 2.1K(t) = -.632 * 2.1

kktt = k = ks s -1.33-1.33

= 11.42 - 1.33 = 10.09mS= 11.42 - 1.33 = 10.09mS

Corresponding time from experimental data:Corresponding time from experimental data:

TT3 3 = 11min= 11min


Finding time constant from experimental Finding time constant from experimental data for dead time coil.data for dead time coil.



Y(t)/A = .632Y(t)/A = .632

Where,Where,


And,And,



Calculating T for dead time coil.Calculating T for dead time coil.

Dead time coil:Dead time coil:K(t) = -.632 * 2.1K(t) = -.632 * 2.1

kktt = k = ks s -1.33-1.33

= 11.42 - 1.33 = 10.09mS= 11.42 - 1.33 = 10.09mS

Corresponding time from experimental data:Corresponding time from experimental data:

TT4 4 = 15min= 15min


Response of tank 3Response of tank 3

C3=Co(Ku-K3/Ku-Ko)C3=Co(Ku-K3/Ku-Ko) (a)(a)

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C4=(Cb-Ca)*(1-exp(t-T4)/T3)+CaC4=(Cb-Ca)*(1-exp(t-T4)/T3)+Ca (b)(b)

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Research paper Research paper Process improvement approach to the saponification reaction by using statistical Process improvement approach to the saponification reaction by using statistical

experimental design.experimental design.Author:Author:

Nihal Bursali a, Suna Ertunc b, Bulent AkaybNihal Bursali a, Suna Ertunc b, Bulent Akayb,,∗∗a a Yenimahalle Municipality Precidency, 06170 Yenimahalle, Ankara, TurkeyYenimahalle Municipality Precidency, 06170 Yenimahalle, Ankara, Turkey

Work:Work:The saponification reaction yields ethyl acetate and ethyl alcohol The saponification reaction yields ethyl acetate and ethyl alcohol which are very useful products.which are very useful products.Therefore, it is quite demanding to determine best operating Therefore, it is quite demanding to determine best operating conditions for the maximum production. Present study is made for conditions for the maximum production. Present study is made for this purpose for the batch saponification reaction. The factors this purpose for the batch saponification reaction. The factors examined are:examined are:Temperature.2.Agitation rate. 3. Initial NaOH concentration. 4. And Temperature.2.Agitation rate. 3. Initial NaOH concentration. 4. And initial CH3COOC2H5 concentration. Selected process response is initial CH3COOC2H5 concentration. Selected process response is conversion of NaOH.conversion of NaOH.””Statistical design of experiments” method has been used to plan Statistical design of experiments” method has been used to plan the experiments to fulfill the purpose of optimization. This is divided the experiments to fulfill the purpose of optimization. This is divided into three phases:into three phases:1-Screening1-Screening 2-Comparing2-Comparing 3-and influence of significant 3-and influence of significant parameters.parameters.


Continued…Continued…At very first, the most effective parameters for process response are detected. The At very first, the most effective parameters for process response are detected. The screening is planned by using the full-two-level factorial experimental design. This screening is planned by using the full-two-level factorial experimental design. This made convenience for evaluating the number of experiments to be performed in a made convenience for evaluating the number of experiments to be performed in a mathematical way. For the four parameters, it gives 2^4=16 experiments. mathematical way. For the four parameters, it gives 2^4=16 experiments. Randomization of experiments is made by using Gnumeric programme of Linux Randomization of experiments is made by using Gnumeric programme of Linux operation system. Temperature and agitation rate were declared to have no effects operation system. Temperature and agitation rate were declared to have no effects on the process response. Sum of squares of factors by using Yates’Alogrithm was on the process response. Sum of squares of factors by using Yates’Alogrithm was used to get the magnitude of effected parameters. Lastly, Variance analysis is made used to get the magnitude of effected parameters. Lastly, Variance analysis is made for comparison. Then, response surface method (RSM) is applied to get optimal for comparison. Then, response surface method (RSM) is applied to get optimal conditions by using the quadratic second order polynomial model. In the response conditions by using the quadratic second order polynomial model. In the response surface method design, Face-centered central composite technique is used to identify surface method design, Face-centered central composite technique is used to identify the second order polynomial model. This helped to illustrate the dependence of the second order polynomial model. This helped to illustrate the dependence of response on significant factors.response on significant factors.The results yielded by the constructed models in this study were checked for The results yielded by the constructed models in this study were checked for adequacy with the help of an efficient model validation test method known as adequacy with the help of an efficient model validation test method known as “Graphical residual analysis”.“Graphical residual analysis”.The maximum conversion of NaOH for the optimum conditions that areThe maximum conversion of NaOH for the optimum conditions that areConc. Of NaOH = 0.01MConc. Of NaOH = 0.01M andand Conc. Of CH3COOC2H5 = 0.1MConc. Of CH3COOC2H5 = 0.1Mis 98%.is 98%.


Section 2:Section 2:Chemical reaction in stirred tank reactors in seriesChemical reaction in stirred tank reactors in series

Sponification reaction:Sponification reaction:

NaOH +CHNaOH +CH33COOCCOOC22HH55 = CH = CH33COONa + COONa +

CC22HH55OHOH


Section2:Section2: Chemical reaction in stirred tank reactors Chemical reaction in stirred tank reactors

in series. in series.

Experiments to optimize the Experiments to optimize the saponification reaction:saponification reaction:

Demonstration of the progress of a Demonstration of the progress of a second order chemical reaction second order chemical reaction through three continuous stirred tank through three continuous stirred tank reactors in series and optimization of reactors in series and optimization of the operating parameters for maximum the operating parameters for maximum conversion .conversion .


Experiment no 5:Experiment no 5:demonstration of the progress of a second order demonstration of the progress of a second order

chemical reaction through three continuous stirred chemical reaction through three continuous stirred tank reactors in series.tank reactors in series.

Procedure:Procedure:1.1. Make up 5 litres batches of 0.05M sodium hydroxide Make up 5 litres batches of 0.05M sodium hydroxide

and 0.05M ethyl acetate.and 0.05M ethyl acetate.2.2. Fill the reagent feed vessels with reactants and refit Fill the reagent feed vessels with reactants and refit

the lids carefully.the lids carefully.3.3. Switch on both feed pumps and agitator motor with Switch on both feed pumps and agitator motor with

specific settings.specific settings.4.4. Start recording the conductivity with respect to timeStart recording the conductivity with respect to time5.5. The conversion is evaluated using the steady state The conversion is evaluated using the steady state

concentration of sodium hydroxide.concentration of sodium hydroxide.6.6. These conductivity measurements at the drain through These conductivity measurements at the drain through

the dead time coil are now to be translated into degree the dead time coil are now to be translated into degree of conversion of the constituents.of conversion of the constituents.


Conclusions and future Conclusions and future suggestionssuggestions

Continuous stirred tank reactors in series have been studied experimentally in detail for Continuous stirred tank reactors in series have been studied experimentally in detail for their dynamic behavior. By introducing the step and impulse input changes in their dynamic behavior. By introducing the step and impulse input changes in concentrations and flow rates of reagents, the system is confirmed to be first order. concentrations and flow rates of reagents, the system is confirmed to be first order. The step and impulse response curves are found to be the sigmoidal and exponential The step and impulse response curves are found to be the sigmoidal and exponential respectively. Furthermore, saponification reaction is carried out and the effects of respectively. Furthermore, saponification reaction is carried out and the effects of parameters are analyzed using the factorial design of experiments method. Best parameters are analyzed using the factorial design of experiments method. Best operating parameters for saponification reaction in CSTRs in series recommended operating parameters for saponification reaction in CSTRs in series recommended are:are:

NaOH Feed Rate NaOH Feed Rate = 45 ml/min, = 45 ml/min,CH3COOC2H5 Feed Rate = 85 ml/minCH3COOC2H5 Feed Rate = 85 ml/min

and Agitators Speed = 9.and Agitators Speed = 9.This combination of factors yielded This combination of factors yielded 96.4 %96.4 % Sodium Hydroxide conversion. Sodium Hydroxide conversion.The ‘reagents concentrations’ and ‘system temperature’ effects have been neglected The ‘reagents concentrations’ and ‘system temperature’ effects have been neglected

during the analysis for optimization, but these may affect the process response during the analysis for optimization, but these may affect the process response considerably. Taking these into account for optimization of process parameters, one considerably. Taking these into account for optimization of process parameters, one may get more beneficial values of conversion.may get more beneficial values of conversion.

First two and the third reactors may be connected in parallel, but obviously will have a low First two and the third reactors may be connected in parallel, but obviously will have a low performance than the existing ones in series.performance than the existing ones in series.


Future workFuture work

Finding rate constant for sponification Finding rate constant for sponification reaction.reaction.

Summarizing of whole work.Summarizing of whole work.

Report preparation.Report preparation.


Reference:Reference:

www.armfield.org.ukwww.armfield.org.uk

PROCESS SYSTEMS ANALYSIS AND CONTROL , Donald R. Coughanowr , 2nd edition.

Equation (a) and (b) , taken from manual of CSTRs in series.


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Continuous Stirrer Tank Reactors in Series