燃煤电厂分离CO_2的经济性分析

Economic analysis on separation of CO_2 from coal-fired power plant

选择装机容量为1000 MW的超超临界燃煤电厂和IGCC电厂作为参考电厂,分析了4种脱碳系统对电厂性能的影响.其中,化学吸收法、膜吸收法脱碳系统和富氧燃烧技术应用于超超临界电厂,IGCC电厂则采用物理吸收法中的Selexol法脱碳.对2种电厂4种工艺的经济性进行了比较,结果显示,超超临界电厂采用化学吸收法或膜吸收法的脱碳费用最高,但是其电厂单位投资最少,厂用电率也最低;而采用富氧燃烧技术虽然脱碳费用较低,但是单位投资较高,脱碳对电厂用电影响最大;IGCC电厂的脱碳费用最低,但是单位投资最高.在超超临界电厂采用的两种吸收法中,膜吸收法的单位投资高于化学吸收法,但运行费用却低于化学吸收法.

With a coal-fired ultra super-critical power plant and an IGCC plant with 1000 MW output chosen as the reference plant, the economic analysis was made for different CO2 removal systems. The chemical absorption, membrane gas absorption and O2/CO2 combustion technology were used in the coal-fired ultra super-critical plant to remove CO2, while the IGCC plant was rebuilt combined with CO2 removal system using physical absorption method. The results showed that the CO2 removal cost of the coal-fired ultra super-critical plant with chemical absorption or membrane absorption methods was highest and yet the capital investment and service power rate were lowest. The cost of CO2 removal using O2/CO2 combustion technology in the ultra super-critical plant was relativity lower, but the capital investment and service power rate was higher. The CO2 removal cost of IGCC plant was relativly lowest, but the capital investment was highest. Compared chemical absorption method and membrane gas absorption method used in the ultra super-critical power plant, the latter has higher capital investment and lower CO2 removal cost.