萃取精馏分离丙酮-正庚烷的模拟与优化

Simulation and Optimization of Extractive Distillation for Separation of Acetone and N-heptane

以丙酸丁酯作为萃取剂,萃取精馏分离丙酮-正庚烷共沸混合物,采用Aspen Plus软件对其过程进行模拟分析,研究设计参数对再沸器热负荷和年度总成本(TAC)的影响,并以最小TAC为目标对萃取精馏过程进行序贯迭代优化。确定优化结果为:萃取精馏塔(EDC)的理论塔板数为43,萃取剂回收塔(ERC)的理论塔板数为32,萃取剂进料位置为第5块塔板,原料进料位置为第38块塔板,ERC的进料位置为第16块塔板,分离得到质量分数为99.5%的丙酮和99.8%的正庚烷。对比优化前后的各评价指标表明:流程优化后TAC节省54.84%,CO_(2)排放量减少60.46%,热力学效率增加155.73%。

Acetone-n-heptane azeotrope was separated by extractive distillation with butyl propionic acid as entrainer.The process was simulated and analyzed by Aspen Plus software.The influence of design parameters on reboiler duty and annual total cost(TAC)were studied.The optimization result is determined:the theoretical plate number of extraction distillation column(EDC)is 43,the theoretical plate number of entrainer recovery column(ERC)is 32,the entrainer feeding position is the 5th plate,the raw material feeding position is the 38th plate,the ERC feeding position is the 16th plate,and the mass fraction of acetone is 99.5%and n-heptane is 99.8%.The comparison of the evaluation indexes before and after optimization shows that:after the process optimization,the TAC savings is 54.84%,the CO_(2)emission is reduced by 60.46%,and the thermodynamic efficiency is increased by 155.73%.