Nonlinear behavior of reactor-separator-recycle systems

The nonlinear behavior of reactor-separator-recycle systems is studied. The dimensionless mole-balance equations are parameterized by the plant Damkoh ler number (Da) and the separation specifications. Reactant accumulation do es not occur if Da > Da(cr). Da(cr) corresponds to a bifurcation point of t he mole-balance equations and depends on separation performance. For one re actant recycle and high purity separation, Da(cr) = 1. When two reactants a re recycled, multiple steady states are possible. In this case, Da(cr) depe nds also on the control structure. Close to Da(cr), control structures must change the reaction volume or temperature in order to reject effectively t he disturbances. (C) 2000 Elsevier Science Ltd. All rights reserved.