醋酸-水萃取精馏萃取剂的选择及过程模拟和优化  

Extractant selection,process simulation and optimization of extractive distillation of acetic acid-water

作　　者：刘绪江 张雷[1] 

机构地区：[1]西南石油大学化学化工学院,四川成都610500

出　　处：《现代化工》2015年第8期165-168,共4页Modern Chemical Industry

摘　　要：基于Aspen Plus软件模拟,对醋酸-水体系进行萃取精馏的萃取剂N-甲基吡咯烷酮、N-甲基乙酰胺、己二腈、ε-己内酰胺4种萃取进行模拟比较,确定己二腈为最佳萃取剂并与文献一直采用N-甲基乙酰胺作为萃取剂相比,产品质量分数更高,塔的再沸器总热负荷为4 436.5 k W,再沸器总热负荷减少了32.1%。同时对己二腈萃取精馏醋酸-水体系模拟优化,参数结果为,萃取精馏塔塔板数为28,原料进料板为第13块,萃取剂的进料板为第3块,回流比为2,溶剂回收塔进料板为第3块,回流比为0.5。此参数下全流程模拟,产品冰醋酸的质量分数达到99.97%,水的出口质量分数达到99.9%。Based on Aspen plus software simulation, four kinds of extractants in the extractive distillation of low concentrations of acetic acid-water system are compared, including N-methylpyrrolidone, N-dimethylacetamide, adiponitrile and 6-caprolactam. Adiponitrile is determined as the best extractant. Comparing with the commonly used N- dimethylacetamide extractant, higher mass fraction of product with adiponitrile as extractant can be achieved. The total columns reboiler heat duty is 4 436. 5 kW and reboiler total heat duty is reduced by 32. 1%. Meanwhile, the extractive distillation of acetic acid-water system using adiponitrile as extractant is simulated and optimized. The optimal conditions for extractive distillation column are shown as follows：28 of stage number, 13 of the raw material feed stage, 3 of extractant feed stage and 2 of the reflux ratio. The parameters for extractant recovery column are shown as follows ：20 of stage number,3 of feed stage and O. 5 of a reflux ratio. Based on whole process simulation parameters,the product of the mass fraction of acetic acid reaches 99. 97% and mass fraction of water outlet reaches 99.9%.

关 键 词：萃取精馏 N-甲基乙酰胺 己二腈 能耗 优化 

分 类 号：TQ028[化学工程]