Process Intensification of Multipressure Reactive Distillation Networks Using Infinite Dimensional State-Space (IDEAS)

The Infinite Dimensional State-Space (IDEAS) conceptual framework is put forward as an intensification tool for the synthesis of globally optimal, multipressure, reactive, azeotropic, distillation networks. To this end, a unit operation model is proposed for reactive vapor–liquid equilibrium flash separators employed as network building blocks, and the concepts of reactive holdup and capacity are introduced as network performance metrics. The method is demonstrated on a case study involving MTBE production using multipressure reactive distillation of methanol/isobutene/MTBE azeotropic mixtures. The globally optimal solutions for the minimum total reactive holdup, minimum total flow, and minimum capacity problems are obtained for a dual-pressure reactive distillation process operating simultaneously at 1.0 and 5.0 atm. For the problem of minimum capacity, the global optimum is found to have both reaction and pressure swing features, indicating those are complementary rather than competing technologies for process intensification purposes.