大型高背压热电联产机组供热季运行分析  

Operation Analysis of Large High Back Pressure Cogeneration Unit in Heating Season

作　　者：栾睎麟 马剑龙[1] 聂深强 丁羿 LUAN Xilin;MA Jianlong;NIE Shenqiang;DING Yi(College of Energy and Power Engineering,Inner Mongolia University of Technology,Hohhot,China,010080)

机构地区：[1]内蒙古工业大学能源与动力工程学院,内蒙古呼和浩特010080

出　　处：《热能动力工程》2024年第9期96-103,共8页Journal of Engineering for Thermal Energy and Power

基　　金：内蒙古自治区科技重大专项项目(2021ZD0036);内蒙古自治区科技计划项目(2023YFHH0070);内蒙古自治区“揭榜挂帅”项目(2023JBGS0012)。

摘　　要：火电厂的冷端损失是电厂热力系统最大的能量损失,汽轮机凝汽器的大量余热通过不同的冷却设备排放至大气中。为降低机组的冷端损失,以某电厂2×350 MW热电联产机组为例,建立高背压余热梯级供热模型,对机组进行高背压供热改造。结合供热季周期供回水温度变化,研究了双抽凝方式(EC-EC)、双抽背串联方式(EHBP-EHBP)在供热季运行时抽汽与负荷分配方式。利用热量法和火用分析法,分析供热机组的经济性与热力学性能。结果表明:高背压串联机组比抽凝机组供热季平均发电功率提升了26.2 MW,平均发电标准煤耗降低了92.0 g/(kW·h),热经济性更好;供热季运行时高背压串联机组比原抽凝机组汽水火用效率平均提升9.6%,额定供暖工况下火用效率提升9.4%。The cold end loss of the thermal power plant is the largest energy loss of the thermal system of the power plant. A large amount of steam turbine condenser waste heat was discharged into the atmosphere through different cooling equipments. In order to reduce the cold end loss of the unit, two 350 MW cogeneration units of a power plant were taken as an example to establish a high back pressure waste heat step-heating model and carry out a study on the high back pressure heating retrofit of the unit. Combined with the temperature change of the periodic supply and return water in the heating season, the extraction and load distribution modes of the double extraction condensation mode(EC-EC) and the double extraction-high back pressure mode(EHBP-EHBP) in the heating season were studied. The economic and thermodynamic performance of the heating unit was analyzed by using the calorimetric method and exergy analysis method. The results show that the average power generation of the high back pressure tandem unit is 26.2 MW higher than that of the extraction condensing unit in the heating season, and the average standard coal consumption of power generation is reduced by 92.0 g/(kW·h), and the thermal economy is better. During the heating season, the steam-water exergy efficiency of the high back pressure tandem unit is 9.6% higher than that of the original extraction condensing unit on average, and the exergy efficiency is increased by 9.4% under the rated heating condition.

关 键 词：热电联产 高背压 供热季运行 经济性 火用效率 

分 类 号：TM621[电气工程—电力系统及自动化]