基于多种供热方式的热电机组运行优化研究

Study on Operation Optimization of Thermoelectric Units Based on Multiple Heating Modes

某电厂用于加热热网循环水的主要设备有热网加热器、热泵机组和高背压凝汽器,热网加热器是通过抽汽直接换热热网循环水使其满足供水温度要求,热泵机组是通过驱动汽源从而高效利用乏汽加热热网循环水,高背压凝汽器是通过提高机组背压从而提高乏汽温度加热热网循环水。以某电厂二期300MW机组供热为例,详细阐述三者在不同供热时段和机组负荷下运行方式的优化配比,通过供热运行方式的优化,4号机组的发电标准煤耗由331.78g/(kW·h)降至168.2g/(kW·h),节能减排效果明显,具有良好的节能效益、环保效益和社会效益。

At present,the main equipment used to heat circulating water in a power plant includes heating network heater,heat pump unit and high back pressure condenser.Heating network heater directly exchanges for hot circulating water by extracting steam to meet the water supply temperature;heat pump unit drives steam source to efficiently use exhaust steam to heat circulating water;high back pressure condenser increases exhaust steam temperature to heat circulating water by increasing unit back pressure.The optimal ratio of the three operation modes in different heating periods and under different unit loads is described in detail based on the heat supply situation of a 300 MW unit in a power plant.Through the optimization of the heat supply operation mode,the standard coal consumption of No.4 unit is reduced from 331.78 g/(kW·h)to 168.2 g/(kW·h).The effect of energy-saving and emissionreduction is obvious,which helps to gain good energy-saving,environmental protection and social benefits.