C_5第2萃取精馏单元过程模拟与优化

Process simulation and optimization of the second extractive distillation unit of C_5 hydrocarbons

介绍了C5第2萃取精馏单元,采用Dortmund修正的UNIFAC基团贡献法预测二甲基甲酰胺-C5体系气液相平衡,修正了Wilson热力学方程中二元交互作用参数,为二甲基甲酰胺萃取精馏分离C5烃类模拟提供了适用的热力学模型。利用Aspen Plus软件,对第2萃取精馏塔进行了模拟分析,考察了萃取精馏塔主要工艺参数溶剂比(质量比)、回流比、进料位置对分离效果和塔热负荷的影响,确定了适宜的工艺操作条件,为节能降耗提供依据。

The second extractive distillation unit of C5 hydrocarbons was introduced, the vapor-liquid equilibrium of dimethylformamide-C5 was predicted by UNIFAC group contribution method, and the binary interaction coefficient in Wilson equation was corrected so as to establish a thermodynamic model based on Wilson equation applicable for simulation of extractive distillation for C5 hydrocarbons with dimethylformamide. With the software Aspen Plus, the simulation analysis of the 2nd extractive distillation column was performed, the influence of such main process parameters like solvent/feed ratio （mass ratio）, reflux ratio and feed position on the separation effect and thermal load of column was investigated, and the proper process operating conditions were determined, thus providing the basis for energy saving and consumption reduction.