半焦和烟煤混合燃料挥发分释放和氮转化特性

摘要/Abstract

摘要： 为半焦在煤粉锅炉中的大比例掺烧应用，以及降低NOx排放，利用管式沉降炉研究烟煤和半焦不同比例混合后挥发分释放特性和氮转化特性。结果表明：温度一定的条件下，混合燃料挥发分的释放率与掺混比例、在炉内的停留时间相关，挥发分的释放率随半焦掺混比例提高而减少，随停留时间的增加而提高，最大挥发分释放率大于其工业分析值。同时，随着半焦掺混比例的增加，混合燃料焦炭氮呈上升趋势，挥发分氮呈减少趋势，当掺混50%半焦时焦炭氮所占比例与原煤相比增加6.08%，NOx排放的控制难度增大。

关键词: 半焦, 烟煤, 掺混, 挥发分释放, 挥发分氮, 焦炭氮, 氮氧化物

Abstract: In order to apply semi coke to pulverized coal boiler in large proportion and reduce NOx emission, the characteristics of devolatilization release and nitrogen conversion after mixing bituminous coal and semi coke in different proportion are studied by using tube furnace bolier. The results show that under certain temperature, the release rate of devolatilization is related to the mixing proportion and the residence time in the furnace. The release rate of devolatilization decreases with the increase of the mixing proportion of semi coke, and increases with the increase of residence time. The maximum release rate of devolatilization is greater than the industrial analysis value. At the same time, with the increase of the blending proportion of semi coke, the coke nitrogen of the mixed fuel shows an upward trend, and the volatile nitrogen shows a downward trend. When 50% semi coke is blended, the proportion of coke nitrogen increases by 6.08% compared with the raw coal, and the difficulty of NOx emission control increases.

Key words: semi coke, bituminous, mix, devolatilization release, volatile nitrogen, char nitrogen, NOx

中图分类号:

TK01

于强王明昊关靖宇贾庚. 半焦和烟煤混合燃料挥发分释放和氮转化特性[J]. 华电技术.

Gaven Jia. Characteristics of devolatilization release and nitrogen transformation in mixture of semi coke and bituminous coal[J]. Huadian Technology.

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