660MW机组联合暖风器系统最佳进水流量研究

Study on optimal inlet flow rate of combined heater system for 660MW unit

以某660 MW机组联合暖风器系统为研究对象,采用现场试验和理论计算相结合的方法,分析运行参数特性。结果表明:闭式暖风器循环水流量越大,系统节能收益越大;随着一级低温省煤器进水温度的提高,系统节能量也相应增加,但当进水温度超过85℃,节能增量变化不大;随着一级低温省煤器进水流量的提升,系统节能量呈现先增大后减小的趋势,存在最佳运行流量;当环境温度提高时,系统节能量表现出相同的变化趋势,且不同环境温度下一级低温省煤器最佳凝结水流量基本一致。

Taking a 660 MW unit combined heater system as the research object,the characteristics of its operating parameters are analyzed by the method of combining field test and theoretical calculation.The results show that the larger the circulating water flow of the air heater,the greater the energy-saving benefit of the system;the energy saving of the system increases with the increase of the inlet water temperature of the primary low temperature economizer,but the energy saving increment changes little when the inlet water temperature exceeds 85℃;with the increase of the inflow flow of the primary low temperature economizer,the energy saving of the system increases first and then decreases,and there is an optimal operating flow;when the ambient temperature increases,the energy saving of the system shows the same change trend as before,and the optimal condensate flow of the primary low temperature economizer is basically the same under different ambient temperatures.