CSTR series arrangement

A reactor system is a series arrangement of a PFR and a CSTR with 10 times the volume of the PFR. A process with rate equation r = 2.4C2 is to be conducted to 96% conversion from an inlet Ca0 = 1. Find the allowable... 

For any series arrangement of CSTRs the overall transfer function is the product of the individual transfer functions. With an impulse input, m<5(t) =... 

The data are from Ref. 31. The objective for optimization is the maximization of the effluent concentration of component B. The performance limit of the system is identihed with each stochastic run requiring an average of only 120 CPU sec on an HP 9000-C100 workstation. Numerous designs are obtained from the stochastic search that perform close to the performance target, mostly variations of series arrangements of PFRs and CSTRs. A detailed discussion of this and other studies is given in Ref. 31. 

Conversion in the series arrangement is greater than in parallel for CSTRs. 

It is common to use several CSTRs in series. When there is only one CSTR, the entire reactor volume is at the lowest concentration, dout, and the reaction rate will be low. Distributing the same total volume over several vessels means that some of the volume will be at higher concentrations and thus higher rates. Of course, the capital cost of the series arrangement will be higher. See Problems 4.19 and 4.20. 

The CIS model is quite simple conceptually. A number iV of CSTRs are arranged in series. Each reactor has the same volume Vor contains the same weight of catalyst W. This configuration is shown schematically in the following figure. 

We have considered two types of ideal flow reactor the piston flow reactor and the perfectly mixed CSTR. These two ideal types can be connected together in a variety of series and parallel arrangements to give composite reactors that are... 

Part (c) considers the mixing extremes possible with the physical arrangement of two tanks in series. The two reactors could be completely segregated so one limit remains 0.233 as calculated in part (b). The other limit corresponds to two CSTRs in series. The first reactor has half the total volume so that Uinkii = 2.5. Its output is 0.463. The second reactor has (ai )2ki2 = 1.16, and its output is 0.275. This is a tighter bound than calculated in part (b). The fraction unreacted must lie between 0.233 and 0.275. 

A second-order reaction of A - B, with fcA = 2.4 L mol 1 h 1, is to be conducted in up to two CSTRs arranged in series. Determine the minimum reactor volume required to achieve 66.7% conversion of A, given that the feed rate and volumetric flow rate at the inlet are 3.75 mol min 1 and 2.5 L min 1, respectively. The feed consists of pure A... 

A particular vessel behavior sometimes can be modelled as a series or parallel arrangement of simpler elements, for example, some combination of a PFR and a CSTR. Such elements can be combined mathematically through their transfer functions which relate the Laplace transforms of input and output signals. In the simplest case the transfer function is obtained by transforming the linear differential equation of the process. The transfer function relation is... 

The final sequence we shall consider is a CSTR and plug-flow reactor in series. There are two ways in wlricb this sequence can be arranged (Figure... 

CSTRs in series. If the 800-gal reactors are arranged in series, the conversion in the first reactor is... 

After completing this chapter you will be able to size CSTRs and PFRs given the rate of reaction as a function of conversion and to calculate the Overall conversion and reactor volumes for reactors arranged in series. 

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