Enviro-economic investigation of Novel heat-integrated configurations for pressure swing distillation

Abstract

Pressure Swing Distillation is a widely adopted solution for the separation of pressure-sensitive azeotropic mixtures in various chemical industries. While this method yields high-purity products, it comes with inherent challenges such as elevated operating costs and energy consumption. However, the temperature differential between the two columns involved presents a compelling opportunity for heat integration. In this study, 18 distinct heat integration scenarios were systematically evaluated using a process simulation software to identify the optimal column configuration for minimizing the Total Annualized Cost. These scenarios span five categories: the Conventional Method, Partial Heat Integration, Full Heat Integration, Internal Heat Integration Distillation Column, and External Heat Integration Distillation Column. The Vapor Recompression Column and Divided Wall Column schemes were applied to each method. Genetic Algorithm served as the optimization tool to determine the best arrangement with TAC as the objective function. Additionally, the environmental impact, assessed through CO₂ emissions, was considered. Results indicate that the most economically and environmentally friendly solution is the I-HIDiC with divided wall columns, incorporating VRC systems in both columns. This approach offers a remarkable 66.5% cost savings and a substantial 96.3% reduction in CO₂ emissions.