利用Aspen Plus流程模拟软件对苯-异丙醇共沸体系进行了热集成变压精馏工艺的分离模拟,采用NRTL-RK活度系数方程作为物性计算模型.确定了热集成变压精馏的压力、工艺流程,分析了进料板位置、回流比等操作参数对分离过程的影响.最佳工艺参数为:常压塔压强采用压强为101.3 kPa,30块理论板数,第15块板进料,回流比为1.8,可在塔釜得到质量分数为99.5%异丙醇;高压塔采用压强为506.5 kPa,30块理论板数,第26块板进料,回流比为3.0,可在塔釜得到质量分数为99.5%苯.模拟结果表明,与常规变压精馏相比较热集成变压精馏可以节省加热蒸汽量以及冷凝水量分别约为53.9%、47.5%,为共沸物系的分离提供了一条有效的节能技术路线.%The benzene-isopropanol azeotropic mixture was simulated for separation with heat-integrated pressure swing distillation by Aspen Plus chemical simulation software, using NRTL-RK activity coefficient equation as the physical model. Pressure and process flowsheet of heat-integrated pressure swing distillation were determined, the effects of feed plate location, reflux ratio and other operating parameters on separation process were analyzed, and the optimum process parameters were obtained as follows: for atmospheric pressure tower , 101.3 kPa, theoretical plates 30, the 15th plate as feed plate, reflux ratio 1.8, the isopropanol of mass fraction of 99.5％ being obtained in the bottom of tower; for a high pressure tower, at 506.5 kPa, theoretical plates 30, the 26th plate as feed plate, reflux ratio 3.0, the benzene of mass fraction of 99.5 ％ being obtained in the bottom of tower. Simulation results showed that the heat-integrated pressure swing distillation could save the quantity of heating vapor and condensing water by about 53.9 ％ and 47.5 ％, respectively, compared with the conventional pressure swing distillation, providing an effective method of energy-saving technologies for the separation of azeotropic system.
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