多煤阶煤粉再燃脱硝特性的试验研究

Experimental Research on Denitrification Characteristics of Pulverized Coal Reburn with Different Coal Ranks

利用管式石英反应器研究了5类煤种的再燃脱硝能力,分析了气流氧含量、煤种挥发分含量、灰分金属氧化物组分对再燃脱硝效果的影响。实验结果表明:随着气流氧含量的升高,挥发分以及焦炭的脱硝效率均降低,但脱硝效率对氧含量的敏感度呈下降趋势;挥发分均相还原所得脱硝效率在实验工况范围内均远高于焦炭非均相还原所得脱硝效率,但其对氧含量的敏感度亦最高;对于所涉及煤种的整体脱硝效率,褐煤最好,烟煤次之,无烟煤最差;煤种挥发分以及某些金属氧化物的含量对脱硝效果起到重要作用,两者缺一则脱硝效率可能明显降低。

Investigation on denitrification effect of pulverized coal reburn with five types of coal ranked from lignite to anthracite was carried out in a quartz tube reactor,and the impact of gas oxygen content,coal＇s volatile matter and metal compounds content in ash on denitrification effect was also analyzed.The experimental results show： with the increasing of oxygen content,the denitrification efficiency of volatile or coke decreases,but the sensitivity of denitrification efficiency to oxygen content presents a trend of decline;volatile＇s homogeneous reduction efficiency,whose sensitivity to oxygen content is maximum,is always higher than coke′s heterogeneous reduction efficiency in all experiment cases;as far as the total reduction efficiency is concerned,lignite′s reduction efficiency is the best and the worst one is anthracite;the content of volatile matter in coal and some metal compounds in coal ash both represent important effect on NOX reduction,the denitrification efficiency maybe decrease evidently if one of these matters was scarce.