燃机余热驱动的部分加热 S-CO₂ 循环多联供系统设计与性能分析

In order to reduce the waste of exhaust heat for the gas turbine, a cogeneration system based on a partial heating supercritical carbon dioxide (S-CO₂) cycle has been proposed to utilize the heat in two stages for achieving a deep recovery. The S-CO₂ containing absorbed heat from the flue gas expands and performs work in the turbine. After releasing heat in the recuperator, it is utilized to power the absorption heat pump., which can improve the utilization of exhaust heat and significantly reduce the cooling loss of S-CO₂. The main operation parameters have been optimized with the objective of maximum profit. Besides, the thermodynamic and economic performance has been analyzed. A 5MW-class gas turbine has been selected as the study object, and the results show that the annual profit of 11.27 million yuan can be obtained when the optimized parameters are adopted. The proposed system has great economic benefits with a dynamic payback period of 5 years, and the net present value through the lifetime reaches 65.30 million yuan. The annual energy utilization efficiency is 67.52% at the design condition, and the annual exergy efficiency is 51.41%, which verifies the remarkability of waste heat recovery for gas turbines. The compressor inlet parameters have a larger impact on system performance, the temperature affects more than pressure, and the economy is the most sensitive to parameter changes.