变压分离甲醇与碳酸二甲酯的工艺模拟

Simulation of Pressure-swing Distillation for Separation of Methanol and Dimethyl Carbonate

在甲醇氧化羰基化法生产工艺中,会产生甲醇和碳酸二甲酯的共沸物,针对甲醇-碳酸二甲酯共沸体系的分离,建立了一种加压-常压的变压分离工艺,采用Wilson模型,在Aspen Plus模拟软件上进行模拟计算,对加压塔和常压塔的回流比、理论板数、进料位置进行了灵敏度分析,确定了最佳工艺参数:高压塔操作压力1.00 MPa,回流比2,理论板34,第25块理论板进料;常压塔操作压力0.10 MPa,回流比4,理论板32,第14块理论板进料;高压塔塔釜可得到合格的碳酸二甲酯产品,低压塔塔釜可得到合格的甲醇产品。

In the process of oxidative carbonylation of methanol to dimethyl carbonate,the azeotrope of methanol and dimethyl carbonate would be formed. In view of the azeotrope of methanol and dimethyl carbonate,a process of pressurized column and atmospheric column was established. With the Wilson model,the separation process was simulated by Aspen Plus. The sensitivity analysis about reflux ratio,theoretical stage number and feed stage was discussed. The best process parameters were as follows,for pressurized column,the pressure is 1. 00 MPa,reflux ratio is 2,theoretical stage number is 34,feed stage is 25; for atmospheric column,the pressure is 0. 10 MPa,reflux ratio is 4,theoretical stage number is 32,feed stage is14. Qualified dimethyl carbonate was obtained from pressurized column and qualified methanol was obtained from atmospheric column.