燃尽风对NOx和CO浓度场分布影响的研究

Research of Effect on NOx and CO Concentration Field Distribution of Over Fired Air

根据燃煤锅炉氮氧化物(NOx)的生成机理,阐述了锅炉对NOx的控制方法主要是分级燃烧,并以实际工程作为依托,综合比较了燃尽风不同的布置方式,高度位置和过量空气系数对锅炉出口NOx和CO浓度场分布造成的不同影响。最终根据CFD模拟,得出过量空气系数对锅炉出口NOx和CO浓度场分布影响较小,而燃尽风采用墙式布置,同时布置在所有扰流之上时,可以保证此时的NOx和CO的浓度分布最低且较为均匀,从而降低锅炉出口NOx的排放,有效提高后续脱硝设备的脱硝效率。

According to the generating mechanism of nitrogen oxides(NOx)in coal-fired boiler,it expounds the NOx control method is graded combustion,and as per actual project,comprehensive comparison of the over fired air in different arrangement,height position and excess air coefficient caused the effect for NOx and carbon monoxide(CO)concentration field distribution.Finally according to the CFD simulation shown,excess air coefficient of boiler export less effect NOx and CO concentration field distribution,and wall type of over fired air,and arranged beyond all fluid flow,to ensure the lowest NOx and CO concentration distribution and relatively uniform,finally reducing NOx emission of boiler outlet,improve the subsequent SCR efficiency of equipment.