Abstract: The energy flow is densitive and the parasitic energy is high for the CO2 capture process with MEA (monoethanolamine) method in power plant. The energy saving based on process integration is important. The characteristics of the grand composite curve justifies the nature of high energy consumption of the CO2 capture process. The pinch analysis of heat exchange net shows the heat transfer across the pinch point. The heat exchange net is optimized and the energy saving projects are: (1) Above the pinch point, the high temperature heat energy from the MEA lean solvent is recovered for the heating of regeneration gas from the pre-absorption tower; (2) Below the pinch point, an ammonia absorption refrigerator driven by the heat of the wet CO2 mixture from the MEA stripper, and the original cold utility for the CO2 liquification is reduced by 43.4%. The energy saving projects based on process integration can reduce the steam consumption and cooling water by 21% and 17.2%, respectively.

Key words: CO2 capture, pinch analysis, process integration, energy saving, parasitic energy

摘要： 电厂一乙醇胺（MEA）法烟气CO2捕集（CCS）工艺换热网络能量流密集，固有能耗高，对该工艺进行过程集成节能研究，具有重要意义。对CO2捕集工艺换热网络的夹点分析说明该换热网络存在跨越夹点的热量传递。冷热物流的总复合曲线特征说明了CO2捕集工艺固有能耗高的特性。对换热网络进行调优并提出了节能技术方案：（1）在夹点之上利用MEA贫液的部分高温位热量加热预吸附塔再生气；(2)采用MEA再生塔产生的湿CO2混合物作为驱动热源，跨越夹点设置一台氨吸收式制冷机以替代CO2液化所需部分制冷量。基于过程集成节能提出的换热集成节能措施可有效降低CO2捕集工艺固有能耗，使蒸汽耗量降低21%,冷却水耗量降低17.2%，CO2液化所需低温冷却公用工程降低43.4%。

关键词: CO2捕集, 夹点分析, 过程集成, 节能, 固有能耗