基于热能深度梯级利用的耦合供热变工况研究

为了实现燃煤机组节能减碳，提出了基于热能深度梯级利用的热电联产机组耦合供热系统，建立了基于热分析法的热电联产机组供电和供热能耗评价模型，基于热力系统集成优化软件（thermal power integration scheme, TPIS）仿真计算了热电联产机组耦合供热系统的能耗，研究了耦合供热系统的变工况运行能耗，结果表明：不同耦合供热方式变工况运行可实现供水温度范围为44~90℃，热指数随着机组负荷升降呈现不同的变化趋势，不同耦合供热方式的机组热效率均随着600 MW亚临界湿冷机组的负荷增加而降低，均随着660 MW超临界空冷机组的负荷增加而增加，机组热效率为63%~80%。研究成果可为热电联产机组变工况运行优化和节能减碳提供技术支撑。

Research on Coupling Heating under Varying Duty Based on the In-Depth Cascade Utilization of Heat Energy

In order to achieve the goal of energy-saving and carbon reduction for coal-fired units, a coupled heating system based on deep cascade utilization of thermal energy is proposed in this paper. The model is first established for the assessment of power supply and heating energy consumption of cogeneration unit by applying thermal analysis method. Then on the basis of the calculation of energy consumption of the coupled heating system using thermal power integration scheme Software (TPIS), the operating energy consumption of the coupled heating system under varying duty is studied. The results show that the temperature of water supply can be adjusted ranging from 44℃ to 90℃ by virtue of different coupled heating methods under variable parameter operation conditions. The thermal index varies in a different way as the unit load goes up or down. Regardless of different coupled heating methods implemented, the thermal efficiencies all decrease with the load increase at unit one, while they all increase with the load increase at unit three, and the unit thermal efficiencies vary from 63% to 80%. The study results are technically supportive of the variable operation optimization of cogeneration units, energy saving and carbon reduction.