CIESC Journal ›› 2020, Vol. 71 ›› Issue (4): 1657-1665.DOI: 10.11949/0438-1157.20191392

• Separation engineering • Previous Articles     Next Articles

Propylene oxide offgas recovery and purification process with methanol solvent

Song HU1(),Jinlong LI2,Weisheng YANG1()   

  1. 1.State Key Laboratory of Green Chemical Engineering and Industrial Catalysis, SINOPEC Shanghai Research Institute of Petrochemical Technology, Shanghai 201208, China
    2.School of Petrochemical Engineering, Changzhou University, Changzhou 213164, Jiangsu, China
  • Received:2019-11-15 Revised:2020-01-07 Online:2020-04-05 Published:2020-04-05
  • Contact: Weisheng YANG

环氧丙烷尾气甲醇吸收及纯化工艺

胡松1(),李进龙2,杨卫胜1()   

  1. 1.中国石油化工股份有限公司上海石油化工研究院,绿色化工与工业催化国家重点实验室,上海 201208
    2.常州大学石油化工学院,江苏 常州 213164
  • 通讯作者: 杨卫胜
  • 作者简介:胡松(1983—),男,博士,高工,husong.sshy@sinopec.com
  • 基金资助:
    国家自然科学基金项目(21878025)

Abstract:

Aiming at the difficulty of recovering the propylene oxide tail gas in the process of producing propylene oxide by the hydrogen peroxide method, a new propylene oxide recovery process using methanol in the reaction unit as the absorbent and extraction distillation column in the refining unit as the desorption tower was proposed. The reactions of both PO hydrolysis and PO and methanol reaction without catalyst were considered and the high-value product of propylene glycol monomethyl ether was additionally obtained through azeotropic distillation technology. The simulation and design optimization for the full process using Aspen Plus package with NRTL thermodynamic model was carried out, and the influence of the main technological parameters, such as solvent ratio, the number of theoretical plates, and the feed temperature of methanol was discussed. The calculations showed that the mass recovery yield of PO was up to 99.99%. The presented process would play an important role in product capacity improvement, energy saving and volatile organic compounds (VOCs) treatment in HPPO plant.

Key words: hydrogen peroxide process, propylene oxide, absorption, extractive distillation, azeotrope separation

摘要:

针对环氧丙烷生产中环氧丙烷尾气难回收问题,提出了甲醇吸收和环氧丙烷萃取精馏解吸回收的环氧丙烷回收新工艺。该工艺同时考虑无催化环氧丙烷水解和与甲醇反应,并采用共沸精馏分离获得高附加值产品丙二醇单甲醚。选用NRTL热力学方法,对上述流程进行了全流程模拟和优化设计,分析了溶剂比、理论塔板数、吸收剂进料温度等主要工艺参数对分离的影响规律,发现新工艺对环氧丙烷质量回收率达到99.99%。研究结果对环氧丙烷工业装置产能提升、节能降耗和挥发性有机物(VOCS)治理具有指导作用。

关键词: 双氧水法, 环氧丙烷, 吸收, 萃取精馏, 共沸分离

CLC Number: