Continuous stirred tank reactor terms

Nomura and Fujita (12), Dougherty (13-14), and Storti et al. (12). Space does not permit a review of each of these papers. This paper presents the development of a more extensive model in terms of particle formation mechanism, copolymer kinetic mechanism, applicability to intervals I, II and III, and the capability to simulate batch, semibatch, or continuous stirred tank reactors (CSTR). Our aim has been to combine into a single coherent model the best aspects of previous models together with the coagulative nucleation theory of Feeney et al. (8-9) in order to enhance our understanding of... 

For steady-state operation of a continuous stirred-tank reactor or continuous stirred-tank reactor cascade, there is no change in conditions with respect to time, and therefore the accumulation term is zero. Under transient conditions, the full form of the equation, involving all four terms, must be employed. 

For a simple A -t- B —> C reaction in a continuous stirred-tank reactor, as shown in Fig. 5.134, in terms of fraction conversion of the reactant A, the balance... 

The residence time distribution for a continuous stirred tank reactor may be represented in terms of the F(t) curve as... 

As mentioned in Section 7.2.1, a well-mixed stirred-tank reactor, when used continuously, is termed a continuous stirred-tank reactor (CSTR). Similarly, a well-mixed stirred-tank fermentor used continuously is termed a continuous stirred-tank fermentor (CSTF). If cell death is neglected, the cell balance for a CSTF is given as... 

The semibatch reactor is a cross between an ordinary batch reactor and a continuous-stirred tank reactor. The reactor has continuous input of reactant through the course of the batch run with no output stream. Another possibility for semibatch operation is continuous withdrawal of product with no addition of reactant. Due to the crossover between the other ideal reactor types, the semibatch uses all of the terms in the general energy and material balances. This results in more complex mathematical expressions. Since the single continuous stream may be either an input or an output, the form of the equations depends upon the particular mode of operation. 

The vector c in Eq. (5) describes the creation in, and/or removal of latex particles from, the system. The creation component may arise from in situ particle formation in Interval I) or from the flow behavior in a continuous stirred-tank reactor system (CSTR) with an arbitrary number of reaction vessels. Particle removal terms may be required if coagulation occurs or in the context of CSTR operation. 

Continuous stirred tank reactor In the case of CSTR, the change of concentration of a substrate S within the reactor ( accumulation ) is brought about by two terms ... 

In writing the material balance equations for a compartment, several assumptions are made. The transport terms between each of the subcompartments are defined, the binding of drug in each subcompartment is quantified and incorporated into the equations, and additional terms are included where necessary to account for liver clearance, kidney clearance, and intestinal absorption. Each subcompartment, i.e., the vascular, the interstitial, and the intracellular, is considered to be a perfectly mixed continuous-stirred-tank reactor (CSTR). This means the concentration of each subcompartment has no spatial dependence. 

In Example 6.4 we developed the linearized model of a continuous stirred tank reactor in terms of deviation variables, given by eqs. (6.36) and (6.37). After rearranging the terms in these equations, we take... 

For a closed chemical system with a mass action rate law satisfying detailed balance these kinetic equations have a unique stable (thermodynamic) equilibrium, lim c( )=Cgq. In general, however, we shall be concerned with chemical reactions that are maintained far from chemical equilibrium by flows of reagents intoand out of a continuously stirred tank reactor (CSTR). In this case the chemical kinetic equation (C3.6.1) must be supplemented with flow terms... 

Finally, several alternate names have been used for what here is called the perfectly mixed flow reactor. One of the earliest was continuous stirred tank-reactor, or CSTR, which some have modified to continuous flow stirred tank reactor, or CFSTR. Other names are backmix reactor, mixed flow reactor, and ideal stirred tank reactor. All of these terms appear in the literature, and must be recognized. 

Semibatch and continuous stirred-tank reactors (CSTRs) are much more commonly found in polyolefin production. Semibatch reactors are the standard choice for laboratory-scale polymerizations, while CSTRs dominate industrial production, as will be seen in Section 2.5. The equations derived above are easily translated into semibatch and CSTR operation mode by simply adding terms for the inflow and outflow streams in the reactor. For instance, consider Equation 2.49 for the zeroth moment of dead chains. The molar flow rate [mol s ] leaving the reactor is given by... 

Lee and co-workers (Lee et al., 2007 Lee, Li, Noike, 2009) describe the continuous H2 production in a continuously stirred tank reactor coupled with a submerged hollow-fibre membrane unit. The presence of the membrane module integrated within the reaction volume allows reducing biomass washout at a high hydraulic retention time with a general improvement of the reactor performance in terms of H2 productivity and yield. 

A similar approach, starting with a material balance, can be used for the characterization of bioreactors operating in the continuous mode. Thus, for a perfectly mixed reactor, or continuous stirred tank reactor (CSTR), where the term of accumulation is zero at steady state and the liquid composition is uniform, the material balance for substrate A is given by Equation 7.7 ... 

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