Continuous stirred tank reactor CSTR tests

Subsequent laboratory continuous stirred tank reactor (CSTR) tests showed that in generating the waste solids CaSOi was being precipitated along with the CaSC>3 even though the solution was not saturated with respect to CaSOi. Thus suggesting the possibility that the precipitation of CaSO involved the formation of some sort of solid solution in the CaSC>3 1/2 H2O lattice. 

The catalyzed oxidation of ethanol to acetic acid is a well-studied reaction, carried out in continuous stirred tank reactors (CSTR) [51]. Hence it is a good test reaction for benchmarking micro reactor results. 

In addition to the above investigations, free-radical high-pressure polymerizations should also be studied in continuously operated devices for three reasons. (1) Because of the wealth of kinetic information contained in the polymer properties, product characterization is mandatory. Sufficient quantities of polymer, produced under well defined conditions of temperature, pressure, and monomer conversion, are best provided by continuous polymerization, preferably in a continuously stirred tank reactor (CSTR). (2) Copolymerization of monomers that have rather dissimilar reactivity ratios, such as in ethene-acry-late systems, will yield chemically inhomogeneous material if the reaction is carried out in a batch-type reactor up to moderate conversion. To obtain larger quantities of copolymer of analytical value, the copolymerization has to be performed in a CSTR. (3) Technical polymerizations are exclusively run as continuous processes. Thus, in order to stay sufficiently close to the application and to investigate aspects of technical polymerizations, such as testing initiators and initiation strategies, fundamental research into these processes should, at least in part, be carried out in continuously operated devices. 

A test problem comparing the analytical and numerical solutions of the same problem using a finite element model 12) is illustrated in Figure 2. The solution corresponds to the case of a continuously stirred tank reactor (CSTR) in which first-order kinetics are assumed, and the rates of reaction are comparable to those we have observed in the laboratory (5,10). 

In the following discussion, we will detail the results and operational experiences the enhanced SBCR system. Objectives of the ran were to 1) test the new slurry level control system 2) compare the performance of a precipitated Fe/K Fischer Tropsch Synthesis (FTS) catalyst in the enhanced SBCR and a continuous stirred tank reactor (CSTR) and 3) determine the effectiveness of the catalyst/wax filtration system. 

The pharmaceuticals company AstraZeneca has recently reported on research that has taken place over a number of years in addressing a switch from batch or semibatch processing to continuous operation. Wemersson (2007) stated that continuous stirred tank reactors (CSTRs), tubular reactors and micro-reactors had been evaluated. Substantial testing has also been done using the Alfa Laval plate reactor (see Chapter 5). Critical variables examined as a function of reactor type have included heat transfer capacity, mixing capacity and flow characteristics. 

We show an example of shape insensitivity by comparing the behavior of the two commonly used models shown in Figure 8.5 continuous stirred tank reactors, CSTRs, and plug flow reactors, PFRs. Here, the mean residence time of the test system is again defined as... 

The experimental unit, shown on the previous page, is the simplest assembly that can be used for high-pressure kinetic studies and catalyst testing. The experimental method is measurement of the rate of reaction in a CSTR (Continuous Stirred Tank Reactor) by a steady-state method. 

In this short initial communication we wish to describe a general purpose continuous-flow stirred-tank reactor (CSTR) system which incorporates a digital computer for supervisory control purposes and which has been constructed for use with radical and other polymerization processes. The performance of the system has been tested by attempting to control the MWD of the product from free-radically initiated solution polymerizations of methyl methacrylate (MMA) using oscillatory feed-forward control strategies for the reagent feeds. This reaction has been selected for study because of the ease of experimentation which it affords and because the theoretical aspects of the control of MWD in radical polymerizations has attracted much attention in the scientific literature. 

The new PI process is performed in three continuous stirred tank reactors placed in series with air flowing countercurrently. As mentioned, the various process functions are activation of linseed oil in the first CSTR (where linseed oil preoxidation takes place autocatalytically at a lower temperature, thereby deactivating the antioxidants), oxidation in the second reactor (mixing of tall oil and activated linseed oil creates a medium wherein components are oxidized and the polymerization is also initiated), and polymerization in the third reactor. A pilot unit with a reactor volume of 2.5 L was built and tested by Forbo Linoleum, Netherlands. The product was converted into linoleum, and its properties were found to be in the acceptable range. 

Batch, recirculating batch, extractive semibatch, semicontinuous flow, continuously stirred tank (CSTR) and continuous packed bed reactors have alt been succesfully tested as enzyme reactors for SCFs (Figure 4.9-1). References to helpful descriptions for designing small-scale reactors for enzymatic studies are collected in Table 4.9-1. 

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