中小型烟煤层燃炉NO_x排放因子的研究

NO_x Emission Factors from Medium and Small Layer Burning Boilers Firing Soft Coal

以86台中小型烟煤层燃炉(额定出力≤65 MW)的燃料特性和NOx排放实测数据为基础,采用统计分析方法,分析了锅炉出力、过量空气系数、燃煤挥发分〔w(挥发分)〕和燃煤含氮量〔w(N)〕对NOx排放因子的影响,研究了NOx排放因子的确定方法.结果表明:中小型烟煤层燃炉基于燃料消耗量、低位发热量和燃煤w(N)的NOx排放因子EFC,EFH和EFN的平均值分别为3.87 g/kg,185.01 ng/J和0.47 kg/kg;锅炉出力对NOx排放因子没有显著影响;NOx排放因子随燃煤w(挥发分)增高而降低;随过量空气系数和燃煤w(N)增大,NOx排放因子的EFC和EFH增高,而EFN并不受影响.

The influences of boiler output, excess air coefficient, coal volatility and nitrogen content on NOx emission factors were investigated using statistical analysis of NOx field data and coal analysis data from 86 medium and small layer burning boilers firing soft coal. The actual capacity of the boilers was ≤65 MW. A methodology for determining NOx emission factors was developed and studied, and NOx emission factors for medium and small layer burning boilers firing soft coal in China were obtained. The results indicated that the uncontrolled average NOx emission factors EFc , EFn , and EFN based on fuel consumption, coal lower beating value and nitrogen content were 3.87 g/kg, 185.01 ng/J, and 0.47 kg/kg, respectively, for medium and small layer burning boilers firing soft coal in China. The NOx emission factors were not significantly affected by boiler output, and decreased with increasing coal volatility. The NO, emission factors EFc and EFH increased with increasing excess air coefficient and coal nitrogen content, but the NOx emission factor EFN was not affected by the excess air coefficient or coal nitrogen content.