The paper constructs the innovative supercritical carbon dioxide (S-CO₂) cycle and boiler coupling thermodynamic model, based on comprehensive system analysis of the S-CO₂ cycle, S-CO₂ boiler and medium temperature heat recovery. The results reveal that moderate cycle maximum pressure and single reheat cycle configuration show the higher cycle efficiency for S-CO₂ cycle with the high boiler pressure drop. High temperature flue gas recirculation mode with large proportion and double rectangular furnace boiler layout can increase the boiler heating surface area and lower the heat duty distribution within S-CO₂ boiler, which can eliminate the impact of excessive mass flow and increased average endothermic temperature in the S-CO₂ cycle. Besides, the system design method and economic evaluation of S-CO₂ coal-fired power plants have been constructed. Single split flow cycle configuration is recommended for the 300 MW S-CO₂ power plants. And double split flow cycle configuration is compulsory for 1000 MW power plants, showing 50.13% overall power plant net efficiency and 0.705 CNY/kW·h levelized cost of energy (LCOE) at 620°C/32 MPa. As for the 600 MW capacity power plants, the former configuration considers the boiler heating exchanger layout simplicity, and the latter configuration increases 0.36% overall power plant net efficiency.

在对S-CO ₂循环，S-CO ₂锅炉和中温热回收进行综合系统分析的基础上，构建了创新的超临界二氧化碳（S-CO ₂）循环和锅炉耦合热力学模型。结果表明，适中的循环最大压力和单次再热循环配置显示了在锅炉压降较高的情况下，S-CO ₂循环的循环效率更高。大比例高温烟气再循环模式和双矩形炉锅炉布局可增加锅炉受热面积并降低S-CO ₂内的热负荷分布锅炉，可以消除S-CO ₂循环中过大的质量流量和平均吸热温度升高的影响。此外，还建立了S-CO ₂燃煤电厂的系统设计方法和经济评价。对于300 MW S-CO ₂电厂，建议采用单分流循环配置。1000 MW电厂必须强制采用双分流循环配置，在620°C / 32 MPa时，电厂总净效率为50.13％，平均能源成本（LCOE）为0.705 CNY / kW·h。至于600兆瓦容量的发电厂，前一种配置考虑了锅炉换热器布局的简化，而后一种配置则提高了0.36％的整体发电厂净效率。