600MW超临界供热机组能量梯级利用及对比分析  

Energy Cascade Utilization and Comparative Analysis of 600 MW Supercritical Heating Unit

作　　者：莫子渊 顾煜炯[1] 陆树银 耿直 MO Ziyuan;GU Yujiong;LU Shuyin;GENG Zhi(School of Energy Power and Mechanical Engineering,North China Electric Power University,Beijing 102206,China;School of Aeronautical Engineering,Zhengzhou University of Aeronautics,Zhengzhou 450046,China)

机构地区：[1]华北电力大学能源动力与机械工程学院,北京102206 [2]郑州航空工业管理学院航空工程学院,河南郑州450046

出　　处：《电力科学与工程》2021年第4期55-62,共8页Electric Power Science and Engineering

基　　金：北京市自然科学基金(3172031);河南省住房城乡建设科技计划项目(HNJS-2020-K08);河南省重点研发与推广专项(科技攻关)项目(212102210009)。

摘　　要：供热机组的合理改造可以节约能源提升热电厂效益。以某600MW超临界机组为基础进行改造,加入耦合吸收式热泵和螺杆膨胀机,并构建了系统的Ebsilon仿真模型,分析得到了系统各热力性能参数和热经济参数随热网回水温度的变化关系。将改造机组和传统供热机组比较,获得了机组优化具体结果。结果表明:热网回水温度升高,系统热力性能恶化,经济性降低。在额定工况下改造机组相比传统机组发电标准煤耗率降低了4.891 g/kW·h,当两者都在最大抽汽量时,可多提供54 MW供热负荷,供热面积增大112.3万m2;在供热负荷都为500 MW、供热面积都为1 041.7万m2时,改造供热机组可比抽汽供热机组少抽汽64.708 t/h。运行过程中螺杆膨胀机一直能保持㶲效率较高的状态,表明其在品位不高能源利用上的优势。研究结果可为热电联产机组的供热改造提供一定的参考。Reasonable transformation of heating units can save energy and improve the efficiency of thermal power plants.Based on a 600 MW supercritical unit,an Ebsilon simulation model was transformed,coupled with an absorption heat pump and a screw expander.The relationship between the thermal performance parameters and thermal economic parameters of the system with the return water temperature of the heating network was analyzed.Through comparing the modified unit with the traditional heating unit,the specific results of unit optimization were obtained.The results show that when the return water temperature of the heating network increases,the thermal performance of the system deteriorates,and the economy decreases.Under rated conditions,the standard coal consumption rate of the modified unit for power generation is reduced by 4.891 g/kW·h,compared with the traditional unit.When both are at the maximum extraction capacity,the modified unit can provide an additional 54 MW heating load and increase the heating area by 1.123 million m2.When the heating load is 500 MW and the heating area is 10.417 million m2,the modified heat supply unit can extract less steam at 64.708 t/h than the extraction heat supply unit.During operation process,the screw expander has been able to maintain a high exergy efficiency state,indicating its advantage in low-grade energy utilization.The research results can provide a certain reference for the heat supply transformation of the cogeneration unit.

关 键 词：热电联产 吸收式热泵 螺杆膨胀机 热力性能 热经济性 

分 类 号：TM621[电气工程—电力系统及自动化]