高温空气燃烧NOx排放特性的试验研究

通过两种结构烧嘴的热态燃烧试验对比,研究了烧嘴结构、燃气射流速度、过量空气系数对高温空气燃烧过程氮氧化物排放的影响特性。研究结果认为:在燃气喷口两侧布置两个矩形空气喷口的烧嘴,氮氧化物排放量低于圆形空气喷口烧嘴;随着燃气射流速度的提高,高温空气燃烧过程排放的氮氧化物逐渐减少。与普通燃烧过程不同的是,随着过量空气系数的提高,在一定范围内高温空气燃烧的氮氧化物排放量不断增加。分析认为,高温空气燃烧氮氧化物排放量与火焰体积、炉内氧气与燃气混合过程以及燃气射流和空气射流对炉内烟气的卷吸量有关。

EXPERIMENTAL STUDY ON THE NOx EMISSION OF HIGH TEMPERATURE AIR COMBUSTION

Some tests of high temperature air combustion were carried out. The effects of nozzle structure, fuel gas injection velocity and excess air coefficient on NOx emission in high temperature air combustion were investigated. The results show that NOx emission was abated when the nozzle with two circle air jet was converted into the nozzle with two rectangular air jet. NOx emission was decreased with the fuel gas injection velocity increasing. But NOx emission was increased with the excess air coefficient rising, which is contrary to the traditional combustion. The analysis were conducted that NOx emission in high temperature air combustion had relations with the volume of flame, mixing process of oxygen with fuel gas, the entrainment of fuel gas injection and air injection with flue gas.