摘要
对煤燃烧过程中燃料型氮氧化物的形成机理及其消除进行了分析。利用挥发分N转化为NO时对沿炉膛高度过量空气系数十分敏感这一特点,在煤燃烧过程中设法建立α<1的富燃料区,使燃料氮在其中尽可能多地转化成挥发分N,同时又促使转化的挥发分N在还原性气氛条件下转变为分子氮(N2),从而达到较大幅度降低氮氧化物之目的。在某热电厂220 t/h锅炉上进行了二次风分级配风燃烧试验研究,研究结果表明:三层二次风燃烧器配风方式采取从下至上依次空气分级送入的方式NOx排放量最低,采用腰鼓型配风方式NOx排放量最高。飞灰含碳量与氮氧化物生成规律正好相反。
The mechanism of fuel -type NOx formation in combustion process of coal and its elimination have been analysed. Using the feature of excess air coefficient,which is very sensitive along the height of furnace in the event of volatile N being converted into NOx a rich- fuel zone of a〈1 has been tried to establish in the combustion process of coal,making the fuel N in said zone to be converted into volatile N as completely as possible,at the same time,promoting the volatile N to be converted into N2 under condition of reducrive atmosphere,thereby, to reach the purpose of greatly decreasing NOx. A test study on combustion with staged distribution of the secondary air has been carried out on a 220 t/h boiler in one power plant, results of study show that the emission of NOx is the lowest under condition of adopting air - distributing mode for three - level＇s secondary air burners according to succesively staged air - feeding mode from bottom to top,and the emission of NOx is the highest under condition of adopting the waist - drum type air - distributing mode. The formation regularity of carbon content in fly ash is just inverse with that of NOx.
出处
《热力发电》
CAS
北大核心
2008年第5期36-39,共4页
Thermal Power Generation
关键词
煤燃烧
燃烧器
NOX排放
分级配风
combustion of coal
burner
emission of NOx
staged air- distribution
