Abstract: As the azeotropic composition of ethylenediamine-water system is sensitive to pressure, a pressure-swing distillation process with partial heat integrated was proposed to separate the azeotrope. First, the steady state simulation of this system was performed by Aspen Plus, and then the optimal design model of separation system for this azeotrope was established, where the total annual cost(TAC) was treated as objective function, the theoretical stage number of tower, feed stage and reflux ratio were adopted as variables, and the purity of products was used as constraint. The line-up competition algorithm was presented to obtain the optimum operation parameters and equipment parameters of the separation system. Simulation results showed that the simultaneous optimization of multiple variables can achieve a more economical separation system as compared with the traditional optimization results, where the TAC can be reduced by about 7.31%. On this basis, improving the operating pressure of the higher pressure column from 2 atm to 4 atm and optimizing the other parameters of the process can significantly reduce the TAC by about 24.62%. Moreover, through partial heat integration, the TAC is further reduced by about 21.87% compared with the one without heat integration.

Key words: pressure-swing distillation, azeotrope, line-up competition algorithm, heat-integrated, optimization

摘要： 针对乙二胺-水共沸物组成对压力较为敏感的特性，采用部分热集成变压精馏工艺分离该共沸物。先利用Aspen Plus软件对该工艺进行稳态模拟，再以理论塔板数、进料位置、回流比为优化变量，水和乙二胺的纯度为约束，以年度总费用（total annual cost，TAC）为目标函数建立乙二胺-水共沸体系分离系统的优化设计模型。采用列队竞争算法对该分离过程主要工艺参数进行优化，得到了变压精馏分离乙二胺-水体系的最佳工艺操作参数及设备参数。模拟结果表明，利用算法对多变量进行同时优化可得到更具经济效益的分离系统，与传统优化结果相比，可降低TAC约7.31%。在此基础上，对高压塔的操作压力进行优化分析，将其由2atm提升至4atm（1atm=101325Pa），并对流程其他参数进行优化，可显著降低TAC约24.62%。进一步，采用部分热集成比普通变压双塔精馏降低TAC约21.87%

关键词: 变压精馏, 共沸物, 列队竞争算法, 热集成, 优化