Improving the Economy, Environmental Sustainability, and Energy Efficiency of Separating Acetone/N-Heptane Binary Azeotrope Via Extractive Dividing Wall Column

To the authors’ knowledge, most research to date has concerned the conventional extractive distillation (CED) to separate acetone/ n -heptane binary azeotrope. In this paper, the extractive dividing wall column (EDWC) technique is utilized aiming at improving the economy, environmental sustainability, and energy efficiency of the separation process. CED process as a benchmark case is simulated and analysed firstly. Then, an energy-efficient EDWC scheme is applied to the process for the separation at a target purity of more than 99.5 mass% for each component. Special attention is paid on the EDWC with heat integration (EDWC-HI) which is designed to recover the waste heat in the cooler for the recycled solvent. This strategy leads to a further reduction in energy consumption. Both of CED and EDWC configurations are optimized following a sequential iterative optimization procedure minimizing the total annual cost (TAC). The proposed EDWC configurations were finally compared with reference to the existing CED process from the economic cost estimation to the environmental evaluation and the energy efficiency