(23c) Energy Savings in Distillation Via Identification of Useful Configurations

Agrawal, R., Purdue University

Recent market and environmental forces require the rapid development of better and cheaper separation process solutions. However, current industrial practice to design separation processes is far from optimal. It relies on the inventive activity of a few experienced engineers. The primary reason for this is the absence of a systematic method to draw and design a multicomponent separation sequence. Even for a commonly perceived ?mature? technology such as distillation, until recently there has been an absence of a method to elucidate all possible multicomponent separation schemes. This talk will focus on multicomponent continuous distillation. A method to draw multicomponent distillation configurations will be introduced. It is known that the number of possible distillation configurations increases rapidly in hundreds and thousands as the number of components in a component mixture increase beyond three (3). Therefore, the first challenge for a process engineer is to be able to draw all feasible configurations and then narrow down the search to a set of suitable candidates. A systematic procedure to draw distillation column configurations to separate an ideal to near ideal component mixture into product streams each enriched in one of the components will be presented. The method is simple and easy to use. The advantage of such a method is that it is easily incorporated in a search algorithm to systematically find an optimum distillation scheme for a given application. Finally, the multicomponent separation method for distillation will be extended to other separation processes such as those based on membranes. It will be shown that the methodology is quite general and can even generate useful hybrid schemes involving different separation processes.