煤基含氮合成气一步法制二甲醚工艺的模拟与优化

Simulation and optimization of one-step synthesis of dimethyl ether from coal-based nitrogen-containing syngas

利用Aspen Plus化工流程模拟软件对煤基含氮合成气一步法合成二甲醚的工艺进行了模拟与优化,结合二甲醚合成的反应动力学方程选择了平推流反应器模型,探讨了反应压力、反应温度对二甲醚产量、CO转化率和产物分布的影响,并通过灵敏度分析对其进行了优化。研究了精馏塔的回流比、理论板数和进料位置等因素对二甲醚吸收和精馏过程的效果和能耗影响,得到了高纯度、低能耗二甲醚生产的最优操作条件。

One-step process for synthesis of dimethyl ether(DME） from coal-based nitrogen-containing syngas is simulated and optimized by Aspen Plus chemical process simulation software.A plug flow reactor model is selected for the synthesis of dimethyl ether according to the kinetic equations. The effects of reaction temperature and pressure on the production of DME,conversion rate of CO and products distribution are investigated and the operation parameters are optimized through sensitivity analysis. In the separation and purification system,DME is set as the component dividing point to separate products.The influences of the using amount of absorbent in absorption tower,reflux ratio,the number of theoretical plate and the feeding position in distillation column on the efficiency and energy consumption of DME absorption and distillation process are studied.The optimal operating conditions are obtained for low energy consumption synthesis of high pure DME.