Optimal Design of Reactive Dividing Wall Column Integrated with a Heat Pump for Two Series Transesterifications

Abstract

This study addresses the integration of a vapor recompression heat pump (VRHP) with a reactive dividing wall column (RDWC) for consecutive multi-component reactions. Two consecutive transesterifications of dimethyl carbonate (DMC) and ethanol were selected for the system. This system has a minimum azeotropic unstable node between the by-product methanol and heavy reactant DMC, while diethyl carbonate (DEC), the final desired product, is the only stable node. As a result of the sensitivity analysis on the DMC mole fraction above the reaction region in RDWC, the location of the reaction region and feed stages affects the purity of the top product due to the azeotropic unstable node. Vapor recompression heat pump (VRHP) was integrated into the RDWC, and optimized with respect to the gas influx into the compressor. The energy consumption in the RDWC integrated with a VRHP is reduced by 32.1% compared to the bare RDWC case.