不同负荷工况下660 MW循环流化床锅炉脱硝特性研究  

Study on denitration characteristic of 660 MW circulating fluidized bed boiler under different load condition

作　　者：张文祥 徐文韬 黄亚继[2] 金保昇[2] ZHANG Wenxiang;XU Wentao;HUANG Yaji;JIN Baosheng(Sujin Shuozhou Coal Gangue Power Generation Co.,Ltd.,Shuozhou 036000,China;Key Laboratory of Energy Heat Conversion and Process Measurement and Control,Southeast University,Ministry of Education,Nanjing 210096,China)

机构地区：[1]苏晋朔州煤矸石发电有限公司,山西朔州036000 [2]能源热转换及其过程测控教育部重点实验室(东南大学),江苏南京210096

出　　处：《电力科技与环保》2024年第1期60-67,共8页Electric Power Technology and Environmental Protection

基　　金：江苏省科技成果转化专项资金(BA2020001)。

摘　　要：为揭示不同负荷下循环流化床的运行特性,以某660 MW循环流化床锅炉为研究对象,在满负荷、75%负荷下,具体研究床温波动、风量配比、烟气含氧量和风煤配比对选择性非催化还原(selective non-catalytic reduction,SNCR)技术喷氨量和脱硝效果的影响。结果表明:满负荷运行时,在欠氧区,SNCR投射喷氨量与循环流化床锅炉给煤量保持同向变化趋势,若持续提高喷氨量,会导致氨逃逸较大,降低SNCR脱硝能力;当炉内给煤量保持稳定,在欠氧还原区内,适当提高二次风量(含氧量),会促进挥发分N的还原反应。75%负荷运行时,床温波动范围超过110℃时,为了满足脱硝要求,应适当提高一次风量、降低二次风量和喷氨量;床温波动范围低于50℃时,应适当降低一次风量和喷氨量;床温波动范围在50~100℃时,应适当降低二次风量和喷氨量;欠氧区内,喷氨量随总给煤量增多而增大。研究结果可以指导循环流化床优化运行,减少氮氧化物排放。In order to reveal the operating characteristics of circulating fluidized bed under different loads,a 660 MW circulating fluidized bed boiler was taken as the research object.Under full load and 75%load,the effects of bed temperature fluctuation,air volume ratio,flue gas oxygen content and air-coal ratio on ammonia injection and denitrification effect of selective non-catalytic reduction technology were studied.The results showed that during full load operation,the ammonia injection projected by SNCR maintained the same trend as the coal feed of the circulating fluidized bed boiler in the oxygen deficient zone.If the ammonia injection is continuously increased,it would lead to significant ammonia escape and reduce the SNCR denitrification capacity.If the coal feeding amount remained stable in the furnace,increasing the secondary air volume(oxygen content)in the oxygen deficient reduction zone appropriately would promote the reduction reaction of volatile nitrogen.During 75%running load,to meet the denitrification requirements,when the bed temperature fluctuation exceeds 110℃,it was necessary to increase the primary air volume,reduce the secondary air volume and spray ammonia appropriately.When the bed temperature fluctuation was below 50℃,the primary air volume and ammonia injection amount should be decreased appropriately.If the fluctuation range of bed temperature was higher than 50℃and lower than 100℃,the secondary air volume and ammonia injection amount should be reduced appropriately.In the oxygen deficient zone,the ammonia injection amount was increased when the total coal amount was increases.The research results can guide the optimal operation of circulating fluidized bed to reduce nitrogen oxide emissions.

关 键 词：循环流化床 脱硝 床温 风量配比 烟气含氧量 风煤配比 

分 类 号：TK229[动力工程及工程热物理—动力机械及工程]