Chapter 15 - Design of reactors and mixers

Abstract

A wide range of proprietary vessel designs are used to carry out chemical reactions. Chemical reactor design must consider the process reaction kinetics, as well as mass transfer, mixing, heat transfer for addition or removal of heat of reaction, and special considerations for catalysis or biological reactions. A general procedure for reactor design is given. Common types of reactor are described. Sources of reaction engineering data and choice of reaction conditions such as temperature, pressure, phase and mixing are discussed. Design of mixing systems for gases, liquids and slurries is described and correlations for agitator power consumption are given. The design of heat transfer to reacting systems and use of heat exchangers as reactors are addressed. An introduction to multiphase reactors is given, with primary focus on gas-liquid reactors and fluidized-bed reactors. The use of homogeneous and heterogeneous catalysis is discussed and procedures given for the design of catalytic reactors. The design of reactors for biological systems such as enzyme catalyzed reactions, fermentation and cell culture is discussed, including particular requirements for sterile processing and cleaning and sterilization of bioreactors. The design of multifunctional batch reactors is described. A brief overview is given of methods for computer modelling of reactors and for scaling up reactor designs from the laboratory to production scale. The use of inherently-safer design principles in reactor design is discussed.