A novel intermediate heat exchange intensified extractive pressure-swing distillation process for efficiently separating n-hexane-tetrahydrofuran-ethanol

• Published in: Chemical engineering science Vol. 300; p. 120593
• Main Authors: Wang, Yumeng, Xu, Hongbo, Yang, Qiyan, Wang, Wenxin, Li, Haixia, Wang, Yinglong, Zhu, Zhaoyou, Li, Xin, Song, Xudong, Cui, Peizhe
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 05.12.2024
• Subjects: Extractive pressure-swing distillation; Intensified strategy; Performance analysis; Process optimization; PSD; NSGA-II; Process optimization; EG; AD; DMSO; Extractive pressure-swing distillation; MGas; Intensified strategy; EtOH; TOC; IHE-EPSD; VR-EPSD; COPs; THF; HI-IHE-EPSD; TCC; TAC; NRTL; 1,2-PDO; Performance analysis; EPSD; ED
• ISSN: 0009-2509; 1873-4405
• DOI: 10.1016/j.ces.2024.120593

•A new intermediate heat exchange distillation process was developed and optimized.•The heat exchange stage and flow rate are determined as the 48th stage and 81kmol/h.•Heat integrated distillation processes were designed to save more energy.•The best intermediate heat exchange process saves 28.6% of energy consumption. The new intensified strategy can be used in special distillation processes to achieve energy savings. Through analyzing the influence of different extractants and pressure on the separation performance of n-hexane-tetrahydrofuran-ethanol. system, extractive pressure-swing distillation process (EPSD) using dimethyl sulfoxide as extractant was proposed. Multi-objective optimization was performed to definite the best operating parameters of EPSD. Based on the phenomenon that the temperature of high-temperature column top is lower than low-temperature column bottom, making it impossible to perform traditional thermal integration, an intermediate heat exchange intensified process (IHE-EPSD) was developed. The performance influencing factors and heat exchange network of IHE-EPSD were analyzed to obtained the optimal IHE-EPSD process. Three heat integration schemes of the IHE-EPSD were designed to further save energy consumption. Finally, the processes were assessed from economy, energy, environment and exergy. The results indicate that the IHE-EPSD process exhibits excellent separation performance, achieving the efficient separation of n-hexane-tetrahydrofuran-ethanol.