基于多级蒸汽机械再压缩热泵的稀N,N-二甲基甲酰胺水溶液蒸馏浓缩工艺

Distillation Concentration of Dilute Dimethylformamide Aqueous Solution Based on Multi-Stage Mechanical Vapor Recompression Heat Pump

分析了蒸汽机械再压缩(MVR)热泵蒸馏浓缩工艺的特点和适用工况,以稀N,N-二甲基甲酰胺水溶液的浓缩过程为研究对象,提出了三级MVR热泵蒸馏浓缩工艺。采用Aspen Plus化工流程模拟软件中的严格精馏模块和压缩机模块,以能耗最低为目标函数,对三级MVR热泵蒸馏浓缩工艺和三效蒸馏浓缩工艺分别进行了模拟与优化,得到了合适的工艺操作参数。模拟结果表明,与三效蒸馏浓缩工艺相比,三级MVR热泵蒸馏浓缩工艺节能约83.2%,其平均能效比(压缩机制热量与压缩机输入功率的比)为0.834;多级MVR热泵蒸馏浓缩工艺具有较大的经济优势。

A process for triple-stage mechanical vapor recompression（MVR） heat pump concentration, which was applied to treating dilute dimethylformamide aqueous solution, was presented by the analysis of the characters and working conditions of the MVR heat pump concentration technique. Aimed at the minimum of the energy consumption, the triple-stage MVR heat pump concentration and triple effect concentration were simulated by means of Compr module and Radfrac module of Aspen Plus software, and suitable parameters were obtained. The research results showed that the triple-stage MVR heat pump concentration process could save energy by 83.2% compared with the triple effect concentration, and the average COP（cofficient of performance） reached 0.834.