变压精馏分离正庚烷-异丁醇工艺设计

Design of Pressure-swing Distillation for Separation of N-heptane and Isobutanol

针对分离正庚烷-异丁醇二元共沸体系,建立了变压精馏分离工艺。选用NRTL模型,对加压塔和常压塔的理论塔板数、进料板位置、回流比等主要参数进行了优化,确定了最佳工艺参数:加压塔操作压力500. 0 kPa,回流比4. 1,理论塔板数65,第6块理论板为进料板;常压塔操作压力101. 3 k Pa,回流比1. 3,理论塔板数9,第5块理论板为进料板。该条件下正庚烷、异丁醇产品质量分数均达到了99. 9%,再沸器总热负荷最低。

For the separation of n-heptane-isobutanol binary azeotropic system,a process of pressurized column and atmospheric column was established.With the NRTL model,the main parameters such as the number of theoretical stage,the feed stage,and the reflux ratio of the pressurized and atmospheric column were optimized.The best process parameters were as follows:for pressurized column,the pressure was 500.0 kPa,the reflux ratio was 4.1,the theoretical stage number was 65 and the feed stage was 6;for atmospheric column,the pressure was 101.3 kPa,the reflux ratio was 1.3,the theoretical stage number was 9 and the feed stage was 5.Under this condition,the mass fraction of both n-heptane and isobutanol products was 99.9%,and the reboiler total heat duty reached the lowest value.