600MW超临界W火焰锅炉无烟煤燃烧NO_x释放规律研究

Study on the NO_x emission during the combustion of anthracite coal in 600 MW supercritical pressure W-flame boiler

针对600 MW超临界W火焰锅炉,对炉内劣质无烟煤燃烧和NOx释放规律进行数值模拟,研究了煤粉浓度、一次风速及前后墙配风方式对炉内NOx释放规律的影响。结果表明:提高煤粉浓度可显著降低炉膛出口NOx排放,在锅炉负荷允许范围内,与常规浓度相比,NOx排放量可降低42%;合理选择前后拱一次风速可有效控制炉内NOx生成,存在最佳一次风速;炉膛前后墙配风方式对炉内火焰对称性影响较大,而对NOx生成量影响不大。

In light of a 600 MW supercritical pressure W-flame boiler,the combustion of low-quality anthracite coal and the generation of NOx in the furnace were numerically simulated.The influence of pulverized coal concentration,primary air velocity and the air distribution on the front and rear wall to the generation of NOx was studied.The results indicate that NOx emission at furnace exit can be effectively decreased by increasing the concentration of pulverized coal.Compared with the conventional concentration,NOx emission can be decreased by 42%.The NOx generated in the furnace can be controlled by selecting a reasonable primary air velocity on the front and rear arch,and there is a best primary air velocity.The air distribution on the front and rear wall has great influence on the symmetry of flame in the furnace but has little effect on the generation of NOx.