ZHANG Jiahao,HAN Chaohan,WU Ying,et al. New polygeneration system for CCUS in coal-fired powerplants[J].Clean Coal Technology,2025,31(4):181−192.

Carbon capture and utilization in coal-fired power plants is of great importance for achieving the ‘double carbon’ goal. Toreduce energy consumption and economic cost of Carbon capture and utilization in coal-fired power plants,a new polygeneration schemefor simultaneous generation of electricity,heat and methanol is proposed. Based on oxy-fuel combustion coal-fired power plant,waterelectrolysis of the renewable energy and methanol generation sub-systems,systematic integration and optimization of the polygenerationscheme is conducted by numerical calculation for thermodynamic and techno-economic analyses. For mass balance,CO2 from oxy-fuelcombustion of the coal-fired power plant and H2 from water electrolysis of the renewable energy are used for methanol generation. O2 from water electrolysis of the renewable energy is used for oxy-fuel combustion of the coal-fired power plant. For energy balance,the coal-fired power plant provides electricity and heat for the methanol generation process. Besides,the exhaust energy of the methanol generationprocess is used for additional electricity generation and heat supply. Thermodynamic analysis results show that the nearly 80% of thecaptured CO2 from oxy-fuel combustion of the coal-fired power plant could be used for methanol generation,which proves the excellentmatchup of the proposed scheme. Based on integration and optimization in a gross 600 MWe coal-fired power plant,the net electricoutput,heat supply and methanol generation in the proposed scheme reach 449.06 MWe,217.17 MWth and 201.70 t/h respectively,whichrealizes the polygeneration of electricity,heat and methanol. Techno-economic analysis results illustrate that the electricity cost of theproposed scheme is decreased to 63.26 $/MWh due to additional benefits from heat,which is lower than the conventional electricity cost ofthe coal-fired power plant with CO2 capture. Besides,the methanol cost of the proposed scheme is decreased to 696.71 $/t due to the savedCO2 cost and fuel cost. Besides,the methanol cost is mainly dependent on the H2 price by water electrolysis of renewable energy andreduction of H2 price is significant for industrial application of the proposed scheme.

张佳豪(2004—),男,江苏南通人。E-mail:zjh277410@163.com

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