共沸精馏分离生物醇-水混合物的模拟与优化

Simulation and Optimizationon Separation of Bioalcohol and Water Mixture With Azeotropic Distillation

针对液-液萃取的异丙醇-正丁醇-乙醇-水(IBE-H 2O)体系,采用共沸精馏方法分离其中的水;并利用化工软件Aspen Plus对发酵产物IBE-H 2O体系的分离提纯进行流程模拟,设计了精馏流程,筛选了共沸剂,考察了共沸剂的适宜用量,优化了操作条件,得到了精馏流程最优、最经济的操作条件。结果表明:IBE-H 2O体系分离提纯优选的共沸剂为甲基叔丁基醚(MTBE);最佳精馏流程的共沸剂循环量为58 kmol/h,理论塔板总数为15,进料位置在塔上部第3块塔板处;提纯得到混合醇产品中IBE的摩尔分数可达到99.6%;且此时共沸精馏流程经济最优。

Water in the isopropanol-butanol-ethanol-water(IBE-H 2O)system is separated by azeotropic distillation process after liquid-liquid extraction.Aspen Plus is used to simulate the continuous azotropic distillation process.Effects of entrainer flow rate and output quantity at the bottom and feed location on the product purity and heat duty are analyzed to obtain the optimal operation parameters.Simulation results indicate that methyl tert-butyl ether(MTBE)can be used as azeotropic entrainer.From the simulation results,it can be concluded that the optimum process operation conditions are entrainer flow rate 58 kmol/h,theoretical stage number 15 and feed location 3.At the above operation conditions,99.6%(molar fraction)purity IBE can be achieved,and the best economic performance in the azeotropic distillation process can be obtained,as well.