Process Analysis of Hybrid Separation Processes: Combination of Distillation and Pervaporation

In order to develop more sustainable and economic production processes for chemical and pharmaceutical products, the focus of academic and industrial research is presently set on the investigation of hybrid separation processes. The combination of classical fluid separation processes with innovative membrane processes especially entails strong synergies. Despite all advantages however, the capability of hybrid sepration processes in industrial scale is hardly exploited because of the lack of general design methodologies and detailed process know-how. Therefore, this paper focuses on modelling, simulation and process analysis of hybrid membrane separations namely on distillation and pervaporation. This hybrid process can be applied for the separation of multicomponent azeotropic mixtures without the use of an entrainer. Its application is illustrated by the separation of a non-ideal ternary mixture of acetone, isopropanol and water. The paper describes a simulation tool for pervaporation and vapour permeation. For the stand-alone membrane process the simulation results are in satisfactory agreement with the gained experimental data. A comparison between different model complexities is presented. The process analysis of the hybrid process shows the influence of decisive operational parameters on process performance and its economic potential.