At present, the chemical looping combustion of coal comprises of the following three steps: coal pyrolysis, coal chargasification,and the reaction of coal pyrolysis and gasification products with oxygen carrier. The entire combustion conversion process islimited by the slower coal coke gasification process,which lead to a decrease in combustion efficiency and CO2 capture efficiency. Becauseof the oxygen carrier used in chemical looping oxygen uncoupling combustion with the ability to absorb and release oxygen,coal cokedirectly react with the gaseous oxygen released by the oxygen carrier,avoiding the slower coal coke gasification process and significantlyimproving the fuel conversion rate. This paper builds a 600 MW chemical linked oxygen decoupling coal-fired power generation systemusing CuO/Cu2O as oxygen carrier using Aspen Plus software. Based on the simulation results of the system,energy,exergy,and exergycost analyses were conducted separately. The results show that the net heat efficiency of the chemical looping oxygen uncoupling coal-firedpower generation system is 37.66%; The component with the highest internal exergy loss in the system is the combustion reactor,whichaccounts for 44.23% of the total internal exergy loss in the subsystem. When only the power generation is used as a product,the efficiencyof the chemical looping oxygen uncoupling coal-fired power generation system is 36.27%. If high concentration CO2 is also used as aproduct, the efficiency of the system is 40.47%. In the chemical looping oxygen uncoupling coal-fired power generation system, thecomponent with the largest unit exergy cost is the seventh feedwater heater,followed by the fifth LP turbine,condenser,the first HPturbine and air preheater.

王小雨(1985—),女,湖北宜城人,讲师,博士研究生。E-mail:wangxiaoyurainy@163.com

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WANG Xiaoyu,ZHAO Haibo. Process simulation on chemical looping oxygen uncoupling coal-fired power generation system[J].Clean Coal Technology,2024,30(10):50−58.