Abstract: Capturing CO₂ from coal-fired power plants using monoethanolamine(MEA)solution is a relatively mature and feasible technology at present.However,high energy requirement is its main drawback.The energy requirement can be reduced by modification of process and optimization.A rate-based model in Aspen Plus simulator is used to simulate the conventional flow path and its modification.The process modifications include absorber intercooling,rich split,lean vapor compression,split flow and the combination of rich split and lean vapor compression.The results show that combination of rich split and lean vapor compression as well as the rich split are the first and the second best process improvement,save of regeneration energy and decrease of equivalent work are 28.2% and 19.3% as well as 11.9% and 11.8%,respectively.For lean vapor compression,save of regeneration energy can be up to 14.1%,while the decrease of equivalent work is only 4.1%.The absorber intercooling and split flow is relatively limited for energy saving.

Key words: monoethanolamine, CO₂ capture, flow sheet, regeneration energy

摘要： 采用一乙醇胺(MEA)进行燃煤电厂烟气脱碳是目前比较成熟和可行的技术,但是存在再生能耗高的严重缺陷。胺法脱碳系统流程改进及优化能有效降低再生能耗。应用Aspen Plus软件基于速率模型对传统胺法脱碳流程及其改进流程进行模拟研究。这些改进的流程包括吸收塔中间冷却流程、富液分流流程、贫液蒸汽再压缩流程、分流流程及富液分流与贫液蒸汽再压缩整合流程。研究结果表明:富液分流与贫液蒸汽再压缩整合流程节能效果最好,和传统流程相比再生能耗及等量功分别下降28.2%和11.9%。节能效果其次的是富液分流流程,再生能耗和等量功分别下降19.3%和11.8%。贫液蒸汽再压缩流程使再生能耗下降了14.1%,而等量功只下降了4.1%。吸收塔中间冷却流程和分流流程节能效果比较有限。

关键词: 一乙醇胺, 脱碳, 流程, 再生能耗