Abstract: Aimed at the effects of carbon capture system on the coal-fired unit economy and with a 600 MW supercritical unit as study object，this paper analyzed the coupled manner between the carbon capture after combustion system and the coal-fired unit，established the evaluation heat economy index of the coupled system calculated and analyzed the effects of changing carbon capture rate and the density of monoetharolamine (MEA) on the heat economy，based on the System Sensitivity Analysis method. The research results showed that at a certain MEA density，when the carbon capture rate increased，the whole plant heat efficiency decreased，and the power production standard coal consumption and the whole plant heat consumption increased；and at a certain carbon capture rate，when the MEA density increased，the power production standard coal consumption and the whole plant heat consumption increased accordingly. At MEA density of 30% and a carbon capture rate of 85%，unit heat economy performance reached optimal value，and the whole plant heat efficiency was 36.34%，6.76% lower than the original 43.10%.

Key words: carbon capture ratet, monoetharolamine (MEA), thermal power system, equivalent enthalpy drop method, thermal economic indicators

摘要： 针对碳捕集系统对燃煤机组热经济性影响的问题，以600MW超临界燃煤机组为研究对象，研究了燃烧后碳捕集系统与燃煤机组的热力系统耦合方式，建立了耦合系统热经济性评价指标，利用系统灵敏度分析方法，计算分析了碳捕集率及乙醇胺（MEA）质量分数变化对耦合系统的热经济性的影响。研究结果表明：当MEA质量分数一定时，随着碳捕集率的提高，全厂热效率呈下降趋势，发电标准煤耗及全厂热耗率逐渐升高；当碳捕集率一定时，随着MEA质量分数的提高，全厂热效率逐渐升高，发电标准煤耗及全厂热耗率呈下降趋势；当MEA质量分数为30%，碳捕集率为85%时机组性能最好，此时，耦合系统的全厂热效率为36.34%，与原机组的热效率43.10%相比降低了6.76%。

关键词: 碳捕集率, 乙醇胺, 热力系统, 等效焓降法, 热经济性指标