热泵精馏在三氯氢硅提纯过程中的模拟

Simulation of heat pump distillation in trichlorosilane purification process

运用化工模拟软件Aspen Plus,选用NRTL-RK物性模型和RADFRAC精馏模型,对三氯氢硅精馏塔的两种热泵流程进行了模拟计算,分别是塔顶气体直接压缩式和塔釜液体闪蒸再沸式热泵精馏。对比热泵精馏流程和常规精馏流程,结果表明:对三氯氢硅提纯而言,塔釜液体闪蒸再沸式热泵流程更有利。本研究采用双塔串行流程提纯三氯氢硅,运用塔釜液体闪蒸再沸式热泵精馏技术,优化后的主要操作参数为:T1塔回流比20,节流阀压力180 kPa,压缩机出口压力309 kPa;T2塔回流比5,节流阀压力227 kPa,压缩机出口压力310 kPa。优化后三氯氢硅的一次收率为88.75%,纯度超过99.9999%;在处理量相同情况下,与常规精馏相比,能耗费用节约82%。

Two types of heat pump distillation flow for trichlorosilane purification were simulated by chemical simulation software Aspen Plus with NRTL-RK property and RADFRAC distillation models. One model used the vapor from the top as heat pump medium and the other model used the liquid from the bottom as heat pump medium. The comparison of heat pump distillation and conventional distillation processes showed that the latter had more advantages in trichlorosilane purification. Two-column trichlorosilane refining serial process using the liquid from the bottom as heat pump medium was conducted. The main optimum operation parameters were showed below. T1 column： outlet pressure of compressor was 309 kPa, mole reflux ratio was 20 and throttle valve pressure was 180 kPa; T2 column： outlet pressure of compressor was 310 kPa, mole reflux ratio was 5 and throttle valve pressure was 227 kPa. The yield coefficient more than 99.9999%. Compared with conventional the same handling capacity. of trichlorosilane was 88.75% and its purity was distillation, energy cost saving was about 82% at