煤粉燃烧时NO_x析出规律的试验研究

Experimental Study on the NO_x Releasing from Pulverized Coal Combustion

在一维沉降炉上系统地考察了煤粉燃烧时NOx的沿程排放特性及其影响因素。试验表明,NOx的生成与炉温、煤粉粒度、煤种、过量空气系数等因素密切相关;在其它条件相同的情况下,NOx的生成浓度随过量空气系数的增大而增大;随着温度的升高略有增大;挥发分含量、氮含量高的煤种NOx的生成也相对较多;煤粉燃烧存在一个临界粒径(dc)。当d>dc时,其NOx浓度随粒径的增大而减小;当d<dc时,其NOx浓度随粒径的减小而减小。(通过对NOx生成规律的分析研究,对今后低NOx燃烧技术的改进具有一定的指导意义。)

The behavior of NO_x emission in the furnace burning with pulverized coal and the effect factors have been studied. The results showed that NO_x emissions are close related to the hearth temperature, particle size, coal sort, stoichiometric ratio etc. The NO_x concentration increases with the increase of the furnace temperature, stoichiometric ratio, content of volatile and nitrogen in coal powder. There exists a critical diameter (d_c). If d>d_c, the NO_x concentration reduces with the increase of the pulverized coal size; If d<d_c, the NO_x concentration reduces with the decrease of pulverized coal size. The experimental study on NO_x formation rule will be very important to guide the application of low NO_x combustion technology in future.