MINLP optimization of reactive distillation columns

Reactive distillation, i.e. the simultaneous implementation of reaction and distillation in a counter current column, has proven to be quite advantageous for several reasons. The whole capacity of reactive distillation and its potential for chemical processes can only be shown at optimized reactive distillation processes. This requires a rigorous simulation and optimization of reactive distillation processes which leads to a Mixed Integer Non Linear Programming (MINLP) problem. This MINLP model is based on the concept of equilibrium stages. In addition to the rigorous formulation of the thermodynamic equilibrium it is necessary to develop an appropriate superstructure for the process to be optimized. To guarantee that the superstructure contains all physical relevant process alternatives, the definition of the superstructure is based on a thermodynamic background. The MINLP optimization can be performed with respect to minimum energy requirement or minimum total annual costs. The results are presented for the synthesis of methyl acetate.