What is relation between temperature and time for CSTR (Continuous stirred-tank reactor) by heat balance?
The process of Biomethanation for Distillery Spent Wash Treatment | Raw Spent wash traetmnet in distillery plant | Biogas generation from CSTRBiomethanation Process for Distillery Spent Wash Treatment | CSTRBasic reactions, Design Criteria, Parameter and process of the anaerobic digesterWorking principle, Basic reactions, Design Criteria, Parameter and process of the CSTR (Continuous Stirred Tank Reactor) or anaerobic digesterCSTR | Continuous Stirred Tank Reactor Design Criteria | Anaerobic DigesterFor sugar industry equipment design and drawing calculation and latest technologies purpose please visit our website.sugar Industry technologiesHome
I have a CSTR reactor with an exothermic and second order reaction and a cooling water system. If I wish to increase the flow at the inlet of the reactor by 20%, what should I do to maintain the conversion?
I will answer qualitatively and leave the maths to you.Increasing the flow rate at the inlet will reduce your residence time, conversion will drop. There are a number of things to do.Increase temperatureIncrease reactant concentrationIncrease catalyst amount (presuming a catalytic reaction)Increase reactor volume (presuming reactor is interchangeable) or add another reactor in seriesRecycle (return a part of the exit flow from the reactor back to the inlet line)You don’t give information about the reactor type and phase - this would help a more specific answer.
What is the difference between a continuos stirred-tank reactor (CSTR) and a perfusion reactor for cell culture?
Continuous stirred tank reactors run the duration of the run with the same media that was used during inoculation of the bioreactor (except for feeds). Perfusion reactors use microfiltration (cartridges) to separate the cells from the media. Fresh media can be added to the bioreactor which means a much longer run-time, and more protein production. The current problems with perfusion reactors is that all of this extra media puts a strain on downstream purification departments, and analytical methods departments. Despite this there are many benefits with continuously fed cell culture (perfusion) as compared to fed batch cell culture such as protein stability,and scalability. Perfusion cell culture should become more cost effective very soon, and I believe it is the future of cell culture biologic manufacturing.
How can I find the real volume of a CSTR (continuous stirred-tank reactor)? Should I add any kind of "correction factor" to the project equation?
Hi, Joe. Thanks for the response. Actually, my question is about projecting a CSTR correctly. There is an expression, called "project equation" that relates the vessel volume with income flow and reaction kinetics. The expression is: V = FA0*X/(-rA). FA0 stands for income flow of the reactant A (usually the limitant reagent), X is the expected conversion factor (eg 80%, 90%) and (-rA) is the consumption rate of the reactant A. This last parameter depends on the reaction kinetics and varies for every type of chemical reaction. Well, assuming I know all the three parameters, I am able to find the Volume (V). But, what does it mean? This volume refers to the liquid phase inside the reactor. My question is: Shouldn't I let a headspace above the liquid phase? If so, how big this headspace should be? 10%, 20%, 30%? I've heard that for microbiological reactors we should specify a headspace of 30% due to foaming. But, what about other types of reaction? Is there any standard correction factor for the calculated volume of a CSTR?
What is the reaction during biogas production?
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For the same volume, which reactor has the highest conversion, a CSTR or a PFR? Why?
For same volume of reactor, PFR gives higher conversion compared to CSTR for Positive order reaction.The basic difference between these two types of reactors is that CSTR maintains same concentration at any point in reactor while PFR has no axial mixing and has only radial mixing. CSTR reduces concentration of reactant to minimum in less time than what PFR does. Rate of reaction is directly proportional to reactant concentration for positive order reactions. More the concentration more will be the rate. Hence PFR gives higher conversion than CSTR for positive order reactions.Edit-1: In one of the answers, Didem Zengin has given levenspiel plot for the distinction between two reactors.Please go through the same since graphical representation is more interpretative than theoretical explanation.
What are some heuristics that can be used to approximate macro hydroynamics in stirred tanks or reactors?
There is some coverage of CSTR's (aka CFSTR when I took this course long ago) here Continuous stirred-tank reactor - more here Continuous reactor and here Continuous Stirred Tank Reactors . You need to characterize the reactor you are using for volume vs. volume flow rate to get the mean residence time and then look at the completeness of the reaction in the outflowing product to determine whether you are getting adequate completion. Or if operating on a batch basis, same for the contents after test run intervals. Were you thinking of designing a custom tank and propellor? Perhaps the reactor maker can give you some guidance on this and how they arrived at the designs available. See Page on globalspec.com and Stirred Reactors