Estimation of conversion limits of reversible reactions in nonideal flow reactors

When a fluid flows through a vessel at a constant rate, usually one of two types of idealized flow can be assumed, either plug flow or mixed flow. There are cases however, which cannot be handled using these ideal models, for the flow patterns are not close to either of these limits, thereby giving inaccurate results. It is explained how the required governing equations are derived. Mathematical models used to describe the mixing in continuous flow systems will be developed based on the concepts of age and life expectations. The distribution functions for residence times are determined. These functions are then illustrated by using suitable differential and integral methods to find the theoretical conversions in the extremes. This work will be concerned with the first and second order reversible kinetics of a parallel combination reactor which is a one parameter mathematical model. In the absence of experimental data, the age distribution of the reactants passing through the reactor is assumed to be known. The actual conversions are then found by using the amount of flow through each reactor. The results for different situations are quite satisfactory and indicate that variations of the second order reversible reactions are functions of the rate constants and the order of reaction.