Engineering of stirred reactor

Bakker, A., Laroche, R.D., Wang, M.H. and Calabrese, R.V., 1997. Sliding mesh simulation of laminar flow in stirred reactors. Transactions of the Institution of Chemical Engineers, 75, 42M4. 

Guichardon, P., Falk, L., Fournier, M.C. and Villermaux, J., 1994. Study of micromixing in a liquid-solid suspension in a stirred reactor. American Institute of Chemical Engineers Symposium Series, 299, 123-130. 

The choice of a reactor is usually based on several factors such as the desired production rate, the chemical and physical characteristics of the chemical process, and the risk of hazards for each type of reactor. In general, small production requirements suggest batch or semi-batch reactors, while large production rates are better accommodated in continuous reactors, either plug flow or continuous stirred tank reactors (CSTR). The chemical and physical features that determine the optimum reactor are treated in books on reaction engineering and thus are not considered here. 

Attempts have been made to expand the technique to include the analysis of soil biotransformations f23.29V While the hydrodynamic nature and physical structure of soil systems vary widely and are difficult to establish with certainty, two limiting conditions may be specified. The first is where the soil particles are suspended and all phases are well-mixed. This case is not typically found in nature, but is found in various types of engineered soil-slurry reactors. The reactors currently used in our systems experiments include continuous stirred tank reactors (CSTRs) operated to minimize soil washout. 

In Part IV we repeatedly used box models for describing the dynamics of chemicals in lakes. In this chapter we will summarize this information. As a first step, Fig. 23.1 illustrates the one-box model approach for the average total concentration of a chemical, Ct, in a well-mixed water body such as a pond, a shallow lake, a subcompartment of a deep lake or ocean (e.g., the mixed surface layer), or even an engineered system like a completely stirred reactor. 

Gas-liquid systems of particular interest to the chemical engineer are encountered in bubble columns, spray columns, air lift, falling film, and stirred tank reactors. Usually the form of these reactors corresponds to that of vessels or columns. From the perspective of the chemical engineer, who is concerned with the conversion and selectivity of chemical transformations, it is of utmost importance that an intensive contact between a gas and a liquid be achieved and therefore very often one phase is continuous whereas the other is disperse. Therefore, the interfacial area and the size of the disperse phase elements constitute very important aspects of CFD modeling of these types of systems. 

Westbrook, G. 1960. The simulation, stabilization and optimization of stirred tank reactors on the digital computer, M.S. Thesis. Department of Chemical Engineering, University of Minnesota, Minneapolis, Minnesota. 

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