Systematic structure generation for reactive distillation processes

Abstract

This paper proposes a systematic structure generation method for reactive distillation processes. When a feed composition to the process is given, the maximum degree of conversion and product compositions of the reactive distillation column are calculated by using the method called Static Analysis (SA). In order to derive the results, the SA uses only the information about the physicochemical properties of the reaction mixture and a selected feed composition. From the results obtained by the SA, the entire feed composition region is classified into several subregions, each of which has different product configurations. Then, a specific process structure consisting of two or three columns is generated for each of the feed subregions. Finally, the design parameters of the columns and the operating conditions are determined by a process simulator. The proposed method is applied to three example problems: the production of MTBE, the esterification of methanol and acetic acid, and the hydrolysis of methyl acetate. The results show that many different feasible structures are enumerated systematically, and that most of the infeasible structures can be eliminated before precise simulations are executed. In the SA, unrealistic assumptions such as infinite flow rate in the column are introduced to simplify the analysis. However, for the above-mentioned examples a good agreement between the results of the SA and those obtained by precise simulations is achieved. Thus, it can be concluded that the results obtained by using the SA are reliable and can be widely used to generate feasible structures of RD processes.