基于活度系数方程的芳烃抽提蒸馏工艺模拟研究

Simulation of aromatics extraction distillation processbased on activity coefficient equation

针对芳烃抽提装置抽提蒸馏工艺流程,利用PRO/Ⅱ模拟软件深入地研究了抽提蒸馏塔、非芳烃蒸馏塔和溶剂回收塔等塔设备分离过程。选取了高度非理想体系汽-液相平衡和液-液相平衡计算模型。采用人工从外部输入的方式,输入了多组芳烃、烯烃和溶剂等重要组分的相平衡计算模型所需的活度系数方程参数和无限稀释活度系数,以扩宽模型使用范围。建立了抽提蒸馏塔等塔设备模拟模块。建立了完整的芳烃抽提装置抽提蒸馏工艺流程模拟软件包。经对比,模拟结果与参考数据的偏差在可接受的范围内。软件包可用于装置的工程设计。总结了烷烃、烯烃、环烷烃和芳烃等在环丁砜中的无限稀释活度系数值随各因素的变化规律。

According to the process of extraction distillation in aromatics extraction unit,the separation processes of extraction distillation column,non-aromatic distillation column and solvent recovery column were studied using PRO/Ⅱsimulation software.The models of vapor-liquid equilibrium and liquid-liquid equilibrium for highly non-ideal system were selected.The activity coefficient equation parameters and infinite dilution activity coefficient required for the phase equilibrium calculation model of several important components,such as aromatics,olefins and solvents,were imported through manual external input,the calculation range of the models of vapor-liquid phase equilibrium was widened.The simulation modules of column equipment,such as extraction distillation column was estabilished.A complete simulation software package for the extraction distillation process of aromatics extraction unit was established.After comparison,the deviation between the simulation results and the reference data was acceptable.The software package can be used for the engineering design of the aromatics extraction unit.The variation of infinite dilution activity coefficient of alkanes,olefins,cycloalkanes and aromatics in sulfolane with various factors was summarized.