甲基氯硅烷精馏流程的模拟与优化

采用Aspen plus软件对工业七塔精馏过程进行全流程建模与模拟，优化工艺参数，研究了新的精馏节能工艺。对一甲塔等7个精馏塔采用双因素水平的灵敏度分析，考察了塔釜采出率、回流比、进料位置和塔顶压力对产品浓度和热负荷的影响，确定一甲塔最优的工艺参数：塔釜摩尔采出率为0.92，摩尔回流比为130，塔顶压力为0.18 MPa，总理论板数为400，在210块理论板位置进料。在此基础上，针对高能耗的脱高塔/脱低塔，模拟研究了双效精馏新工艺，新工艺可节省39.70%的年总成本；针对一甲塔模拟研究了热泵精馏新工艺，新工艺可降低41.42%的年总成本。

Simulation and optimization of methylchlorosilane distillation scheme

Methylchlorosilane crude monomer is the mixture of several components with a close boiling point, which demands high mass purity in subsequent polysiloxane polymerization process. Traditionally, seven to ten distillation columns are used to separate these methylchlorosilane components with huge energy consumption. In the field of this research, prevailing industrial seven-column scheme was simulated by using Aspen plus software. The effect of distillation column bottom extraction ratio, reflux ratio, feed stage and top pressure on product concentration and heat duty were studied systematically for the optimization of operation conditions using the method of double factors sensitivity analysis. According to sensitivity analysis, the appropriate operation conditions of Me1 column were as follows, that molar bottom extraction rate was 0.92, molar reflux ratio was 130, feed position was at 210th theoretical stage and top pressure was 0.18 MPa, respectively. According to energy calculation of seven-column scheme, heavies removal column, low removal column and Me1 column took up 96.2% of total heat duty consumption. In order to reduce energy consumption, new energy saving scheme was studied and simulated. Thermodynamic analysis showed that pressure was a non-significant influencing factor for key components separation of heavies removal column and low removal column. So, a more energy-efficient distillation process, double effect distillation, had been studied for two columns to achieve heat integration between heavies removal column condenser and low removal column reboiler. The result of rigorous simulation showed that the new double effect distillation scheme, comparing to original two-column scheme, can reduce total annual cost (TAC) by 39.70%. The thermodynamic analysis of Me1 column showed that relative volatility of key binary components was near 1. So the heat pump distillation scheme had been developed to improve heat efficiency of Me1 column. The result of rigorous simulation showed that heat pump distillation scheme, comparing to original Me1 column scheme, can reduce TAC by 41.42%.