Combustion and Pollutant Emission Characteristics of Lignite Dried by Low Temperature Air
Combustion and Pollutant Emission Characteristics of Lignite Dried by Low Temperature Air
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DOI：
10.1080/07373937.2014.967402
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发表时间：
2015-01-01
影响因子：
3.3
通讯作者：
Che, Defu
中科院分区：
文献类型：
--
作者：
Man, Chengbo;Zhu, Xin;Che, Defu
褐煤是一种水分含量高的煤，在使用前需要干燥。本文研究了我国褐煤在120-180 ℃空气中干燥后的物理化学结构变化。结果表明，干燥后褐煤的孔容和比表面积减小。一些亚甲基和甲基被干燥空气中的氧气氧化，导致氧官能团增加。采用热重分析法研究了干燥煤和母煤（干基）的燃烧特性。干燥煤的总挥发分产率增加相比，母煤。干燥煤的燃尽温度高于母煤，而着火温度几乎保持不变。建立了一套快速热解和燃烧过程中含氮气体产物释放的气流床实验装置。热解过程中干燥煤的HCN产率高于母煤，燃烧过程中NO产率也有类似的变化趋势。根据物理化学结构分析结果，探讨了燃烧机理和污染物排放特性的变化。
Lignite is a kind of coal that has high moisture content and needs to be dried before being utilized. In this article, a Chinese lignite was dried in air at 120-180 degrees C and the changes in its physical and chemical structures after drying were investigated. The results showed that the pore volume and specific surface area of the lignite decreased after drying. Some of the methylene and methyl groups were oxidized by the oxygen in the drying air, resulting in an increase in oxygen functional groups. The combustion characteristics of the dried coals and parent coal (dry basis) were studied via thermogravimetric analysis. The total volatile yields of the dried coals increased compared to the parent coal. The burnout temperatures of the dried coals were higher than the parent coal, whereas the ignition temperatures stayed almost unchanged. An entrained flow system was set up to study the release of nitrogenous gas products during rapid pyrolysis and combustion. The HCN yields of the dried coals during pyrolysis were higher than that of the parent coal, and a similar trend was found for the NO yield during combustion. The mechanism changes of combustion and pollutant emission characteristics were discussed according to the results of the physical and chemical structure analyses.