分级燃烧及煤粉细度对NO_x排放浓度的影响

Effects of Air Staging and Particle Size on NO_x Emissions

在一台９２．９ｋＷ／ｈ的卧式煤粉燃烧炉上进行了不同煤种、不同细度的分级燃烧试验．实验发现：分级燃烧对高挥发分煤种以及同一煤种的细煤粉的ＮＯｘ排放浓度的降低效果更显著；对于同一煤种，细煤粉的飞灰含碳量较粗煤粉低，而且随着分级程度的增加，细煤粉的飞灰含碳量的增加幅度较粗煤粉小；在一次风喷口安装钝体稳燃器时可提高燃烧效率、降低ＮＯｘ．

Investigations on air staging combustion have been carried out using different coals and fineness with a 92.9kw/h tunnel furnace burning pulverized coal. The experimental results have shown that air staging combustion has more remarkable effect on NO x reduction of high volatile coal and fine pulverized coal. For the same coal, the unburned carbon decreased with increasing fineness, and with increasing air staging; for the fine pulverized coal, the increase in unburnt carbon in fly ash is lower than for the coarse pulverized coal. It is also observed that the unburned carbon in fly ash and NO x emissions can be decreased by installing a bluff body in the primary air jet.