水-乙酸甲酯-四氢呋喃三元共沸物系热集成萃取精馏工艺

Heat integrated extractive distillation process for water-methyl acetate-tetrahydrofuran azeotrope system

针对水-乙酸甲酯-四氢呋喃三元共沸体系的特点,提出了热集成萃取精馏工艺对其进行分离研究。选择WILSON热力学模型计算该物系的气液相平衡数据,利用ASPEN PLUS软件中的两相闪蒸模块,模拟得到了不同萃取剂条件下,该物系各共沸组分间的相对挥发度。结果表明,乙二醇作为该物系的萃取剂比较合适,且最佳的溶剂比为0.37。在此基础上,以能耗和年总费用(C_(AT))作为技术经济评价指标,对常规三塔萃取精馏工艺进行了模拟与参数优化,并利用夹点分析技术对精馏系统的换热网络进行了优化。基于换热网络的优化结果,对常规三塔萃取精馏工艺进行了热量集成。研究结果表明,与常规三塔萃取精馏工艺相比,热集成萃取精馏工艺其能耗降低约34.70%,C_(AT)节省约21.98%,热力学效率提高约36.34%。因此,热集成萃取精馏工艺是分离该三元共沸物系比较合适的节能工艺。

In view of the characteristics of the water-methyl acetate-tetrahydrofuran ternary azeotropic system, a heat integrated extractive distillation process was proposed to study its separation. The WILSON thermodynamic model was selected to calculate the vapor-liquid equilibrium data of the system, and the two-phase flash module in ASPEN PLUS software was used to simulate the relative volatility between the azeotropic components for the system under different extractant conditions. The results showed that ethylene glycol was more suitable as the extractant for the system, and the best solvent ratio was 0.37. On this basis, taking energy consumption and annual total cost(C_(AT)) as technical and economic evaluation indicators,the conventional three-column extractive distillation process was simulated and the parameters were optimized,and the heat exchange network of the distillation system was optimized by using pinch point analysis technology.Based on the optimized results of the heat exchange network,the conventional three-column extractive distillation process was integrated with heat.The research results showed that compared with the conventional three-column extractive distillation process,the heat integrated extractive distillation process can reduce energy consumption by about 34.70%,save C_(AT) about 21.98%,and increase thermodynamic efficiency by 36.34%.Therefore,the heat integrated extractive distillation process is a more suitable energy-saving process route for separating the ternary azeotrope system.