煤粉工业锅炉预燃式低氮燃烧器试验研究与开发  

Experimental study and development on a pre-burning low-NO x burner for pulverized coal industry boiler

作　　者：许鑫玮 谭厚章[1] 王学斌[1] 杨富鑫 刘兴[1] 郑海国 XU Xinwei;TAN Houzhang;WANG Xuebin;YANG Fuxin;LIU Xing;ZHENG Haiguo(School of Energy and Power Engineering,Xi′an Jiao Tong University,Xi′an 710049,China;Xi′an Green Power Technology Co.,Ltd.,Xi′an 710065,China)

机构地区：[1]西安交通大学能源与动力工程学院,陕西西安710049 [2]西安格瑞电力科技有限公司,陕西西安710065

出　　处：《洁净煤技术》2020年第5期36-41,共6页Clean Coal Technology

基　　金：国家重点研发计划资助项目(2017YFB0603902)。

摘　　要：日趋严苛的燃煤氮氧化物(NOx)排放标准对煤粉工业锅炉性能提出了较高的要求,我国现有的煤粉工业锅炉燃烧器难以通过运行优化直接达到排放标准。基于此开发了一种用于煤粉工业锅炉的新型预燃式低氮旋流燃烧器,并在25 t/h煤粉工业锅炉上进行试验,研究了一次风率、二次风配比、旋流叶片角度、再循环风(FGR)及燃尽风(OFA)对NOx排放和燃烧效率的影响。结果表明:当一次风率从7.8%增加到8.5%,NOx排放升高;随着内外二次风比从0.67增大到1.32,NOx排放升高;随着旋流叶片角度从30°增大至60°,NOx排放先降低后升高;随着FGR风率从0增加至13.3%,NOx排放逐渐降低并趋于稳定;OFA风量对NOx排放影响不显著,随OFA风量增大,NOx排放总体呈先降低后升高趋势。煤粉工业锅炉试验过程中煤粉气流着火稳定,飞灰含碳量稳定在25%以下;最佳工况的NOx排放值为171~178 mg/m 3(9%O 2),飞灰含碳14.9%,锅炉热效率91.7%。The increasingly strict emission standards on NOxput forward higher requirements for the performances of the coal-fired industrial boilers.It is hard for the existing burners in industrial boilers to meet the emission restrictions by operation optimization.In this study,a new type of coal-fired low-NOxswirling burner for industry boilers was developed.Through the experiments in a 25 t/h industry boiler,the effects of primary air ratio,secondary air distribution,swirling angle,recirculated flue gas(FGR)and over fire air(OFA)ratio on NOxemission and combustion efficiency were studied.The results show that the NOxemission increases when the primary air ratio increases from 7.8%to 8.5%and the inner/outer secondary air ratio increases from 0.67 to 1.32.As the angel of swirl vane increases from 30°to 60°,the NOxemission decreases first and then increases.With the increase of FGR ratio from zero to 13.3%,the NOxemission first decreases and then tends to be stable.The effect from OFA ratio on NOxemission is slight,and with the increase of OFA ratio,the NOxemission first decreases,and then increases.During the test process,the coal stream flame is stable and the unburned carbon content in fly ash(UBC)is always lower than 25%.The lowest NOxemission is obtained as 171-178 mg/m 3(9%O 2),with a UBC value of 14.9%and a boiler efficiency of 91.7%.

关 键 词：煤粉工业锅炉 低氮燃烧器 锅炉效率 配风方式 

分 类 号：X511[环境科学与工程—环境工程]