摘要
随着可再生能源发电比重的增加,火电机组在深度调峰中的重要性日益突出,大幅度变负荷已成为运行常态。为了研究循环流化床(CFB)机组的深度变负荷特性,本文以河坡电厂超临界350 MW机组CFB锅炉为研究对象,分析了CFB机组变负荷时的床温、蒸汽参数以及污染物排放的变化。结果表明:床温与负荷成正相关,前后位置床温的差值相对较大,通过控制排渣量可显著调节床温;随着负荷变化,高温过热器出口蒸汽与高温再热器出口蒸汽的温度整体稳定,波动较小;60%~90%负荷升降负荷时,由于运行床温和二次风配比合理,NO_x排放质量浓度的变化范围分别为30~70 mg/m^3和20~50 mg/m^3,且中低负荷区间变负荷时NOx的原始生成量显著大于中高负荷;在参与深度调峰时负荷响应速度较快,机组升负荷速率为6 MW/min(1.71%/min),降负荷速率为4 MW/min(1.14%/min)。总体而言,超临界350 MW机组CFB锅炉变负荷范围广,低负荷稳定性强,NOx原始排放较低。
With the increase of the proportion of renewable energy generation,the importance of thermal power units in deep peak load regulation is increasingly prominent,and large-scale load change has become the normal operation.In order to study the deep varying load characteristics of circulating fluidized bed(CFB)unit,this paper takes the supercritical 350 MW CFB boiler of Hepo power plant as the research object,analyzes the variations of bed temperature,steam parameters and pollutant emissions at varying load.The results show that,the bed temperature is positively related to the load,and the bed temperature difference between the front and rear positions is relatively large.The bed temperature can be significantly adjusted by controlling the amount of slag discharged.With the load changing,the temperature of the superheated steam and the reheated steam is generally stable with small fluctuation.When the load is increased and decreased between 60%and 90%of the full load,the variation range of NOx mass concentration emission is 30~70 mg/m3 and 20~50 mg/m3,respectively,due to the reasonable bed temperature and secondary air rate.The original NOx formation at varying load in middle and low load range is significantly greater than that at medium and high load.When participating in deep peak load regulation,the load response speed is faster,the unit load increasing rate is 6 MW/min(1.71%/min),and the load decreasing rate is 4 MW/min(1.14%/min).Generally,the supercritical 350 MW CFB boiler has the advantages of wide range for variable load,high stability at low load,and lower original NOx emissions.
作者
蔡晋
单露
王志宁
张缦
金燕
蔡新春
王鹏程
杨海瑞
CAI Jin;SHAN Lu;WANG Zhining;ZHANG Man;JIN Yan;CAI Xinchun;WANG Pengcheng;YANG Hairui(Shanxi Research Institute for Clean Energy,Tsinghua University,Taiyuan 030032,China;Department of Energy and Power Engineering,Tsinghua University,Beijing 100084,China;College of Electrical and Power Engineering,Taiyuan University of Technology,Taiyuan 030024,China;Shanxi Gemeng International Co.,Ltd.,Taiyuan 030001,China;Shanxi Hepo Power Plant Co.,Ltd.,Yangquan 045000,China)
出处
《热力发电》
CAS
北大核心
2020年第9期98-103,108,共7页
Thermal Power Generation
基金
国家重点研发计划项目(2019YFE0102100)。
关键词
超临界
CFB锅炉
深度调峰
变负荷
床温
蒸汽参数
污染物排放
supercritical
CFB boiler
deep peak load regulation
variable load
bed temperature
steam parameter
pollutant emission
