锅炉暖风器通常采用汽轮机抽汽作为热源加热一、二次风，暖风器内抽汽与空气换热温差较大，致使传热不可逆损失较大从而影响机组的整体性能。为了减小暖风器的不可逆损失，提高机组性能，提出将吸收式热泵技术应用于燃煤火力发电系统，采用汽轮机回热抽汽作为热泵驱动热源，以冷凝器循环水作为低温热源，制取中温热水用于加热暖风器内一、二次风，并采用低温省煤器回收烟气余热的技术方案。建立了该方案的物理模型，并分别与另外3种方案进行比较。结果表明，利用吸收式热泵加热燃煤电站一、二次风，并采用低温省煤器回收烟气余热后，汽轮机回热抽汽量减少，机组发电效率升高，热耗率降低，发电煤耗降低1．95 g/kW·h。%To reduce the irreversible losses in the air heater, and improve the thermal efficiency of the plant, this paper proposed a method by utilizing the absorption heat pump in the coal-fired power plant. The extracted steam from the steam turbine acts as the high temperature heat source for the absorption heat pump, while the circulating water from the condenser acts as low temperature heat source. The primary and secondary air is heated by the ab-sorption heat pump. The physical model of a typical 660 MW coal-fired power plant is established. Based on the physical model, the simulation programs of four cases are developed. As a result, the case using the absorption heat pump as the heat source of steam air heater is able to reduce the amount of extracted steam. Besides, the ther-mal efficiency is improved, while the heat rate is reduced, and the coal consumption is reduced by 1. 95 g/kW·h.
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