加热器端差对机组热经济性的影响

Influence of Terminal Temperature Difference on Thermal Economy of Generating Units

为降低机组发电成本,实现提质增效目标,针对机组各加热器类型,计算分析得出加热器端差对机组热经济性影响特性,并通过实验获得控制发电成本手段。结果显示,端差对机组抽汽等效焓降、汽耗率、标准煤耗率的影响随抽汽级数和负荷的变化产生不同影响。在实际运行中,负荷越高能耗敏度越小。但由于负荷越高,端差越大,导致高负荷下端差引起的发电成本增加值越大。试验发现,通过调节高压加热器液位可减小端差,从而降低发电成本。

To reduce the power generating cost and achieve the goal of quality improvement and efficiency increase,the influence characteristics of the heater terminal temperature difference on the thermal economy of the unit are calculated and analyzed according to the heater type of the unit,and the means for generation cost control are obtained through the experiment.The results show that the influence of terminal temperature difference on the equivalent enthalpy drop,vapor consumption rate and standard coal consumption rate of the unit varies with the extraction steam numbers and load.In actual operation,the load varies inversely with energy consumption sensitivity.However,the load increases with terminal temperature difference,leading to an added value increase of power generation cost due to terminal temperature difference under high load.It is found by the test that the level regulation of the high-pressure heater can reduce the terminal temperature difference and can thereby the power generation cost.