煤粉再燃的半工业炉试验

Pulverized coal reburning in a semi-industrial furnace

从系统NOX还原效果,主燃区,再燃区和燃尽区内NOX的分解几方面对煤粉再燃效果进行半工业炉试验研究。虽然主燃区NOX生成量与主燃区过量空气系数成正比,系统NOX还原率却在主燃区过量空气系数=1.10时呈现最大值;再燃区还原性气氛有利于NOX的还原,但富氧氛围也可以实现一定NOX分解,燃尽区内煤粉异相还原占主要地位。以基础工况和再燃工况下的锅炉尾部NOX排放量的差值来计算系统NOX还原率可以更好地体现锅炉系统的再燃脱硝能力。

NOx reduction efficiency and NOx reduction characteristics in primary combustion zone, reburning zone and burnout zone were studied during reburning of pulverized coal in a semi-industrial furnace. NOx production rates increased with the increasing excess air in the primary combustion zone; the highest NOx reduction efficiency was obtained when the primary combustion zone excess air ratio was 1.10. Although a reductive environment in the reburning zone favored NOx reduction, it also took place under an oxygen-rich condition. In the burnout zone, heterogeneous combustion of pulverized coal was the predominant mechanism. The amount of NOx release under the reburning condition relative to that of the baseline condition is a better parameter to represent the NOx reduction capability of the furnace system.