The energy analysis and optimization of process system aiming to solve the problems of high consumption, low efficiency and unreasonable use of energy in the process of energy utilization has been widely researched and developed in recent decades. In this work, advanced exergy analysis was carried out for the triple-column extractive distillation (TCED) process separating ternary azeotropic mixture of ACN/EtOH/H2O. The total exergy destruction is 1097.69 KW. The avoidable exergy destruction, is 29.20%, mainly caused by the cooler and three condensers. Based on the thermodynamic analysis results, a superstructure TCED with four-parallel evaporator organic Rankine cycles (FPE-ORC) system is proposed, four working fluids were selected. An improved genetic algorithm is used to obtain the optimal operating parameters of the ORC system by using the exergy efficiency and annual net profit (ANP) of the ORC as two conflict objective functions. Compare with existing process, the FPE-ORC system with working fluid R600 provides the highest exergy efficiency of 12.27%, with working fluid R600a leads to the best economic benefit of 6.43 E + 4 dollar/year.

旨在解决能源利用过程中高消耗，低效率和不合理使用能源的问题的能源分析和过程系统优化已在近几十年来得到了广泛的研究和发展。在这项工作中，对三塔萃取蒸馏（TCED）过程进行了高级能值分析，以分离ACN / EtOH / H2O的三元共沸混合物。总的火用破坏为1097.69 KW。可避免的火用破坏率为29.20％，主要由冷却器和三个冷凝器引起。基于热力学分析结果，提出了具有四平行蒸发器有机朗肯循环（FPE-ORC）系统的上部结构TCED，选择了四种工作流体。利用改进的遗传算法，以ORC的火用效率和年净利润（ANP）为两个冲突目标函数，获得ORC系统的最优运行参数。与现有工艺相比，带有工作液R600的FPE-ORC系统提供的最高能效效率为12.27％，而工作液R600a带来的最佳经济效益为6.43 E + 4美元/年。