The reactor synthesis problem can simply be stated as follows: Given the reaction mechanism and kinetics, what is the optimum type and arrangement of the reactor(s) that would maximize product yield? Extensive studies for simple reaction systems (series, parallel, consecutive, etc.) using idealized plug flow and continuous stirred tank reactors have been presented in the literature. However, these studies fail to provide a systematic procedure for selecting the reactor(s) type and the arrangement for complex reaction schemes.In this paper simple rules with geometrical interpretations have been developed for synthesizing isothermal reactor configurations for complex reaction schemes. A computer program capable of specifying the optimum reactor structure from a generalized configuration has also been described. SCOPEWhat is the optimum type(s), arrangement, and size of the reactods) that would maximize product yield for a given reaction mechanism? This is the essence of the reactor synthesis problem in the chemical process industry.Previous studies in the reaction engineering field have resulted in some guidelines for simple reactions. These rules and their limitations have been presented in this paper. However, these studies fail to provide a systematic procedure for selecting the reactor(s) type and the arrangement for complex reaction schemes.This paper is the first in a two-part series which attempts to classify reaction schemes into three basic types. Simple rules with geometrical interpretations have been presented for Type I1 reactions and a synthesis computer program has been described for Type 111 reactions. These rules are limited to isothermal reactor systems only. Non-isothermal studies will be presented in Part I1 of this paper. CONCLUSIONS AND SIGNIFICANCEIn this paper reaction schemes have been classified into three basic types based on the kinetic equations: Type I (simple reactions), and Types I1 and I11 (complex reactions).Simple rules for Type I reactions have been presented in this paper. These rules are based on previous studies by Denbigh (196l), Carberry (1966), and others. Rules have been derived for several serial reactor configurations for Type I1 reactions. Geometrical interpretations for these rules have been presented to provide an understanding of the mathematics involved. Fi-nally, for Type I11 reactions, a computer program has been discussed which is capable of specifying the reactor type(s), arrangement, and size for a given reaction mechanism.This work is significant in that it is the first attempt to develop rules for synthesizing reactor configurations for complex reaction schemes. It provides a methodology for specifying the optimum structure of the reactor system for complex reactions which would be necessary in the synthesis and development of chemical process flowsheets.The design of chemical Process reactors has been recognized for a 10% time as an important and difficult Problem, because in-Correspondence concerning this paper should be addressed to Rakesh Govind process an...

No abstract

In Part I of this paper a methodology for the synthesis of optimal isothermal serial reactor structures for complex reactions was presented. This has been extended to nonisothermal systems in this paper.A complete review of the relevant background has been included in this paper. A graphical procedure has been presented for Type I1 complex reactions and a computer program has been described for Type I11 complex reactions. Two cases for the Van de Vusse reaction scheme and a naphthalene oxidation example have been used to illustrate the synthesis approach. S. P. CHITRA and RAKESH GOVIND SCOPEThe objective of this research is to find rules and procedures which could be used in specifying the type and arrangement of reactods) to maximize product yield for complex reactions. In Part I of this paper the methodology presented was limited to isothermal systems. In this paper a methodology has been described for the synthesis of serial nonisothermal reactor SYSterns. CONCLUSIONS AND SIGNIFICANCEIn Part I of this paper reactions were classified into three basic types. Type I reactions were called simple reactions, and Types I1 and I11 were denoted complex reactions.From a literature review summarized in this paper, it has been concluded that the rules presented in the literature for adiabatic and nonadiabatic reactor systems are only applicable for simple reactions and in general are not valid for complex reactions.For Type I1 complex reactions a graphical procedure has been INTRODUCTIONIn Part I of this paper a synthesis strategy was proposed for obtaining the optimum serial reactor structure consisting of isothermal reactors, for a Type I1 complex reaction scheme. An optimization strategy and a computer program was also described for obtaining an optimum serial reactor structure for Type 111 complex reactions.As noted in Part I, the objective of our research is to find rules and procedures which could be used in specifying the type and arrangement of the reactor(s) to maximize product yield for complex reactions.Conespndence concerning this paper should he addressed to Rakesh Govind.AlChE Journal (Vol. 31, No. 2) presented for obtaining the optimum temperature profile. Analytical results for obtaining the optimum serial reactor structure have been derived for Type I1 complex reactions. These results have been explained graphically in the form of a stepping procedure described in this paper.For Type I11 reactions an optimization procedure based on the modified complex method has been used to obtain the optimal serial reactor structure. The dominant eigenvalue method is used to converge the calculations.In this paper, the methodology presented earlier for isothermal serial structures will be extended to nonisotherrnal reactor systems.Although preliminary decisions can be made concerning operating temperature and reactor type based on isothermal operation, ultimately it is important to analyze the nonisothermal nature of the system. All industrial reactions are either exothermic or endothermic, and the associated heat eff...

In this paper, two studies will be presented for the following general reaction.in which the order of the side reaction (A -C) Is higher than the main reaction (A -B). The optimum yield and ideal reactor configurations have been obtained for a wide range of kinetic constants. General conclusions have been drawn that enable the optimum reactor configuration to be deduced directly from the rate curve. In part 2 of this series, these resutts will be extended for nonideal reactors with dispersion in the plug flow reactor and segregation in the continuous stirred tank reactor.

No abstract