ABSTRACT
In Chapters 3 and 4, we developed the conservation equations used to calculate the concentrations and temperatures in reactors that obeyed the ideal reactor assumptions. Recall that in an ideal batch reactor, the contents were assumed to be perfectly mixed, and in šow reactors, the two extremes of plug šow and perfect mixing were used. These assumptions lead to simplicity in the mole and energy balances, and are valid in many industrial reactors, such that it is suf„cient to use an ideal reactor model to analyze and predict the reactor performance to a level acceptable for design calculations. In other cases, however, the deviation from ideal reactor behavior may be suf„ciently large that the use of an ideal reactor model will give an unacceptably large error. Deviations from ideal reactor performance are caused by many factors, and depend on the type of reactor and its mode of operation. The purpose of this chapter is to introduce the methods of analyzing nonideal systems, which can be used either to model a real reactor or to investigate the degree of nonideality of an existing system, with a view to improving its performance. The causes of deviation from the ideal case are „rst summarized, followed by a treatment of some methods of analyzing nonideal reactors. Finally, the topic of mixing is introduced. Note that the modeling of nonideal reactors is a complex subject and far from an exact science. Many techniques have been used to model nonideal reactors and what follows is an introduction to some possible methodology. Further information on the modeling of nonideal systems can be found in Levenspiel (1999) and Froment et al. (2011). A more advanced presentation of mixing in šow systems is given by Nauman and Buffham (1983), while those looking for an in-depth treatment of mixing phenomena can refer to Ottino (1989) or Baldyga and Bourne (1999).
