基于剩余曲线分析和变压精馏分离氯仿-乙腈-乙醇三元体系

Separation Process of Methyl Trichloride-Acetonitrile-Ethanol System by theAnalysis to Residual Curve and Pressure Swing Distillation

利用剩余曲线初步分析氯仿、乙腈和乙醇三元混合物的分离过程。在分离过程中,选择氯仿作为初步分离的共沸剂,根据剩余曲线分析计算得到额外加入氯仿与原料液的最佳质量比为0.64,在此条件下混合物的初步分离过程中,塔顶产物为氯仿-乙醇共沸物,塔底产物为乙腈。再利用变压精馏分离氯仿和乙醇共沸物,高压塔和低压塔压强分别为600 kPa和101.325 kPa。最后利用Aspen Plus对工艺进行模拟和优化,得到最佳操作条件。结果表明,氯仿、乙腈和乙醇的质量含量均大于99%,符合设计要求。

The separation process of the ternary mixture of Methyl trichloride(chloroform)-acetonitrile-ethanol was analyzed by the residual curve.Chloroform was selected as the azeotropic agent for the preliminary separation.According to the analysis of the remaining curve,the best mass ratio of the additional chloroform to the raw material liquid was calculated to be 0.64.The top product was chloroform-ethanol azeotrope and the bottom product is acetonitrile in the preliminary separation process of the mixture under this condition.The azeotrope of chloroform and ethanol was separated by.The pressure-swing distillation of the high-pressure tower is 600 kPa and the pressure of the low-pressure tower is 101.325 kPa.The optimal operating conditions were then obtained by using Aspen Plus to simulate and optimize the process.The results showed that the mass content of chloroform,acetonitrile and ethanol are all more than 99%which meets the design requirements.