MINLP Synthesis of Reactive Distillation Using a Disjunctive, Hybrid Model

In order to develop optimization models for process industries, detailed hybrid modelling providing accurate descriptions of processes is required, where the simplest part of the model is represented explicitly in an equation-oriented environment whilst detailed calculations, e.g. enthalpies, kinetics, equilibrium and efficiencies, are programmed by external implicit functions. The two main objectives of our work have been: i) the development of such hybrid modelling environment, and ii) implementation of efficient solution strategies in an MINLP process synthesizer MIPSYN, the successor of PROSYN (Kravanja and Grossmann, 1994), which could make solving such complex industrial problems possible. The present study focuses on the catalytic distillation processes. Since the use of a multilevel MINLP approach reduces the effects of nonconvexities, better solutions were obtained by multilevel than by single level MINLP strategies.