集成BEST的700℃一次再热超超临界机组回热系统节能优化  

Energy Saving Optimization Study on Regenerative System of 700 ℃ Single Reheat Ultra-supercritical Unit with BEST

作　　者：王婧 段立强[1] 杨金福[2] 杨名 荆雨田 田李果 WANG Jing;DUAN Liqiang;YANG Jinfu;YANG Ming;JING Yutian;TIAN Liguo(School of Energy,Power and Mechanical Engineering,North China Electric Power University,Beijing 102206,China;Institute of Engineering Thermophysics,CAS,Beijing 100190,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]中国科学院工程热物理研究所,北京100190

出　　处：《动力工程学报》2022年第7期632-641,共10页Journal of Chinese Society of Power Engineering

基　　金：国家重点研发计划资助项目(2017YFB0602101、2018YFB0604404)。

摘　　要：针对700℃一次再热超超临界机组回热系统抽汽过热度偏高、[火用]损较大的问题,在基准机组基础上提出2种方案并进行性能对比研究,方案1采用背压抽汽汽轮机(back pressure extraction steam turbine,BEST)替代基准机组3~6级的回热加热器,方案2采用BEST并加装外置式蒸汽冷却器(outer steam coolers,OSC)。采用单耗分析法分析了不同方案在不同负荷下的能耗分布。结果表明:方案1和方案2均能够有效降低回热抽汽过热度;与基准机组相比,方案1、方案2在较高负荷时具有节能优势,在低负荷时基准机组更有节能优势,因此对于700℃一次再热超超临界机组,BEST更适合较高负荷的机组。Aiming at the problems of high extraction superheat and large steam loss in the regenerative system of 700 ℃ single reheat ultra supercritical(USC) unit, two schemes were proposed and compared on the basis of the reference unit, while in scheme 1 the back pressure extraction steam turbine(BEST) was used to instead of stages 3-6 regenerative heater, and in scheme 2 both outer steam coolers(OSC) and BEST were used. The energy consumption distributions of different schemes under variable load were analyzed by using the unit consumption analysis method. Results show that both scheme 1 and scheme 2 can effectively reduce the superheat degrees of regenerative steam extractions and save more energy at higher load compared with the reference unit, but the reference unit has energy-saving advantages at lower load. So the BEST is suitable for higher load operation unit for 700 ℃ single reheat USC power generation system.

关 键 词：一次再热 超超临界机组 BEST 抽汽过热度 单耗分析 

分 类 号：TK212[动力工程及工程热物理—动力机械及工程]