1000MW机组燃烧调整对NO_x排放影响  

Effect of Combustion Adjustment on NO_x Emission in 1 000 MW Unit

作　　者：冯涛[1] 马乐乐[1] 兰勇[1] 王龙飞[1] FENG Tao;MA Lele;LAN Yong;WANG Longfei(North China Electric Power Research Institute(Xi’an)Co.,Ltd.,Xi’an 710065,China)

机构地区：[1]华北电力科学研究院(西安)有限公司,陕西西安710065

出　　处：《锅炉技术》2018年第5期51-54,共4页Boiler Technology

摘　　要：在1 000MW机组锅炉上进行了燃烧调整试验,通过改变过量空气系数、机组负荷、燃尽风率和配风方式,对烟气NO_x的排放规律进行了研究。结果表明:随着过量空气系数的增大,NO_x排放浓度显著增大,锅炉排烟热损失呈上升趋势,飞灰含碳量呈下降趋势。锅炉负荷对NO_x排放的影响主要来自燃料量、炉膛温度、氧浓度等多方面因素的综合影响,随着锅炉负荷下降,过量空气系数增大,烟气NO_x排放浓度呈缓慢下降趋势,单位质量燃料的NO_x转化率有所升高。增大炉膛的燃尽风率可显著降低烟气NO_x排放浓度。在燃尽风率较低的燃烧工况下,NO_x排放浓度对燃尽风率的变化尤为敏感。与均等配风方式相比,束腰配风方式可降低炉膛主燃料区的氧浓度,使烟气NO_x排放浓度下降。Combustion adjustment tests were carried out on a 1 000 MW unit boiler.The emission of NO x from flue gas is studied by changing the excess air coefficient,unit load,over-fire air rate and air distribution.The results indicated that with the increase of excess air coefficient,the concentration of NO x emission increases significantly,the heat loss of the boiler flue gas shows an upward trend,and the carbon content of fly ash decreases.The influence of boiler load on NO x emission mainly comes from the comprehensive influence of the fuel quantity,the temperature of furnace and the oxygen concentration.With the decrease of boiler load,the excess air coefficient increases,the NO x emission concentration of flue gas shows a slow downward trend,and the NO x conversion rate of unit mass fuel is increased.The NO x emission concentration of flue gas decreases significantly with the increasing of over-fire air rate.And the NO x emission concentration is particularly sensitive to the change of over-fire air rate under the condition of low over-fire air rate.The experiments also confirmed that the lower oxygen concentration in the main fuel zone of the furnace and lower NO x emissions occurres in constricted air distribution mode,by comparison,in uniform mode.

关 键 词：1000MW机组 燃烧调整 NOX排放 

分 类 号：TK229.2[动力工程及工程热物理—动力机械及工程]