Superstructure-Based MINLP Formulation for Synthesis of Semicontinuous Mass Exchanger Networks

This paper deals with the synthesis of mass exchanger networks (MENs) for semicontinuous processes. The starts and endings of available process streams are time-dependent since they usually come from other batch plants. A periodically partitioned stagewise superstructure is presented for modeling the time-dependent mass exchange operations. The proposed stagewise superstructure can handle multiple transferable components and can also be extended to include storage tanks. Not using any heuristics that are based on the concepts of pinch point, the proposed superstructure-based representation for synthesis of semicontinuous MENs is formulated as a mixed-integer nonlinear program (MINLP) for targeting the consumption of external lean mass separating agents. The coke oven gases (COGs) problem from the literature is supplied to demonstrate the applicability of the proposed MEN synthesis method for semicontinuous processes.