多晶硅尾气回收精馏工序模拟优化

Simulation and Optimization of Polycrystalline Silicon Exhaust Recycling Section

针对改良西门子法中尾气回收精馏工序的节能要求,用过程模拟软件Aspen Plus对流程进行模拟优化。首先,通过SiHCl3-SiCl4物系汽液平衡实验数据与用不同热力学模型模拟出的汽液平衡数据比较,然后将Aspen软件模拟出的进料物流的热容值与实际计算的热容值进行比较,筛选出了能最佳描述本体系热力学性质的热力学模型RK-Soave,建立了热力学模型;其次,将用Aspen软件模拟得出的进料物流的纯组分密度与查阅文献计算得到的密度进行比较,考查了所选热力学方程的可靠性。对多晶硅尾气回收段的精馏工序进行模拟优化,得出各塔的最优参数。

According to energy saving requirements,the exhaust gas recycling distillation section in modified Siemens process was simulated and optimized using simulation software Aspen Plus.In order to choose the thermodynamic model which can best describe thermodynamic properties of the actual system,first,Vapor-liquid equilibrium data of SiHCl3-SiCl4 get through experiments was compared with the vapor-liquid equilibrium data simulated using different thermodynamic models.Second,the heat capacity value simulated by Aspen was compared with the actual calculated heat capacity value.Third,for investigate the reliability of the selected thermodynamic equations,the density of pure component of the feed stream calculated by Aspen software was compared with the density calculated using expression from literatures.It showed that the RK-Soave equation was optimal for polysilicon exhaust gas recycling section system.The exhaust gas recycling section of polysilicon process was simulated and optimized using RK-Soave equation.