针对膜工业中所产生的质量分数为5%~15%的N，N-二甲基乙酰胺（DMAC）废水，提出了分离DMAC废水减压逆流的双效、三效和四效精馏工艺流程。通过实验和Aspen流程模拟对多效精馏的工艺进行了研究。利用响应面法（RSM）对多效流程进行了优化，以最小年度总费用（TAC）为目标函数，确定了回收废水中DMAC最佳方案为减压逆流三效精馏工艺。

Aiming at treating N,N-dimethylacetamide (DMAC) wastewater with a content of 5%-15% produced in the membrane industry,the double-effect,three-effect and four-effect distillation processes for vacuum countercurrent of DMAC wastewater system are proposed.These multi-effect distillation processes are studied through experiments and Aspen process simulation.Response surface method (RSM) is used to optimize these multi-effect processes.With the minimum total annual cost (TAC) as the objective function,the vacuum countercurrent three-effect distillation process is determined as the best solution for recovering DMAC from wastewater.