煤粉燃烧炉膛沿程NOx释放规律的研究

对一维炉内煤粉燃烧，炉膛沿程NOx的释放规律进行了数值模拟和试验研究。研究结果表明：炉内温度升高，NOx的析出峰值升高，位置前移，温度达到一定值后，随温度的升高, NOx 的释放量又呈下降趋势；煤中含氮量越多，NOx释放量越大，NOx的析出峰值位置，随煤种碳化程度的增加而逐渐后移；随过量空气系数的增加，NOx释放量呈明显增加的趋势；NOx的释放量与煤粉粒度的关系中，存在一个煤粉平均粒度临界值dc，当煤粉粒度d≤dc时，随煤粉粒度的减小，NOx的释放量减小，当煤粉粒度d>dc时，随煤粉粒度的减小，NOx的释放量增大；模拟计算同试验结果吻合较好。

Study on the NOx Release Rule Along Boiler During Pulverized Coal Combustion

Numerical simulation and experimental study on the NOx release rule along boiler during pulverized coal combustion have been done. As the temperature increasing, the peak value of NOx release moves forward，NOx emissions increase. But when the temperature increased to some extent, NOx emissions reduce with the temperature increases. The NOx emissions increase with the nitrogen content of coal increases. The peak value of NOx release moves backwards with the increase of coal rank. NOx emissions increase obviously with the increase of stoichiometric ratio. There exists a critical average diameter (dc). If d≤dc, the NOx emissions reduce with the decrease of pulverized coal size. If d>dc, the NOx emissions reduce with the increase of the pulverized coal size. The results show that overall reasonable agreement between the simulation results and experiment results for concentration distribution of NOx along the axis of furnace is obtained.