二甲醚-甲醇-水体系精馏的实验研究

在装有丝绕矩形螺旋圈填料的精馏塔内进行二甲醚-甲醇-水三元体系精馏实验，原料在填料层的中部加入，在压力0．55MPa-0．95MPa，进料温度20℃～80℃，回流比0．1～0．6，进料中二甲醚摩尔分率0．0705～0．1354的范围内，考察了操作条件对二甲醚精馏的影响。实验结果表明：随着回流比和进料中二甲醚摩尔分率的增加，塔顶二甲醚的含量随之增大；随着操作压力的升高，塔顶二甲醚的含量减小；进料温度不大于70℃为宜。建立了二甲醚精馏塔的平衡级稳态数学模型，采用序贯的循环嵌套迭代计算方法对模型进行求解；结果表明模拟计算值和实验值吻合良好。

Experimental Study on Distillation Process of Dimethyl Ether-Methanol-Water Ternary System

Distillation experiment of dimethyl ether(DME) iscarried out in a tower with wire—coiled rectangle helix ring packing,the feeding liquid is fed into the middle of the packing layer, and theeffects of process parameters on the distillation of DME were investigated under the pressure of 0.55MPa～0.95MPa, the feed temperature of 20°C ～80°C, reflux ratio of 0.1～0.6 and DME mole fractionin feed from 0.070516 to 0.135357. The results showed that theconcentration of DME increases with the increment of reflux ratioand DME mole fraction in feed, and the concentration of DME decrease with the increment of the operation pressure. It is advisablethat feed temperature should be limited to not more than 70°C. Amathematical model was established to research the distillationprocess on the basis of equilibrium stage theory. The cyclical nested—iteration method in sequential convergence was developed to solvethe model equation. The results showed that the simulation valuesfrom the model are in good agreement with the experimental date.