Energy-efficient extractive pressure-swing distillation for separating binary minimum azeotropic mixture dimethyl carbonate and ethanol

Ao Yang, Shirui Sun, Tao Shi, Di Xu, Jingzheng Ren, Weifeng Shen

Research output: Journal article publicationJournal articleAcademic researchpeer-review

40 Citations (Scopus)

Abstract

An energy-efficient extractive pressure-swing distillation process is proposed for separating binary minimum azeotropic mixture ethanol and dimethyl carbonate. It can be observed that the minimum amount flow rate of entrainer will be decreased when the operating pressure of extractive distillation column is increased via the thermodynamic feasibility insights (i.e., residue curve map and isovolatility lines). Therefore, an extractive pressure-swing distillation process with 4 bar for the extractive distillation column is designed. Process variables of the proposed design are optimized by combining the sensitivity analysis and sequence quadratic program approaches with minimum total annual cost as objective function. Total annual cost, CO2 emissions, and exergy loss of the optimized extractive pressure-swing distillation with 4 bar for the extractive distillation column is reduced by 44.09%, 44.16% and 41.54%, respectively when compared with the existing process with 1 bar for the extractive distillation column, which mainly attributing the flow rate of entrainer decreasing from 200.020 kmol/h to 44.963 kmol/h. Furthermore, the extractive pressure-swing distillation with heat integration is studied to further reduce energy cost because the enough heat transfer temperature difference could be provided by increasing operation pressure.

Original languageEnglish
Article number115817
JournalSeparation and Purification Technology
Volume229
DOIs
Publication statusPublished - 15 Dec 2019

Keywords

  • Azeotropic mixture
  • Conceptual design
  • Energy-efficient
  • Extractive pressure-swing distillation
  • Separation

ASJC Scopus subject areas

  • Analytical Chemistry
  • Filtration and Separation

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