煤矸石自燃造成严重的环境和生态问题,为揭示煤矸石自燃宏观特性及微观结构之间的关联性,采用热重-傅里叶红外光谱(TG/FTIR)联用技术及自燃程序升温实验,系统研究了煤矸石自燃氧化过程失重率、气体产生率和官能团变化规律及自燃特性.结果表明,煤矸石中存在次甲基、含氧环烷、醚键等桥键和缩合芳环等物质,自燃氧化过程总失重率30.30%.得到了煤矸石自燃过程中7个特征温度,气体脱附、氧化裂解、燃烧和热活化及相变阶段的失重率分别为1.05%,3.27%,20.36%和5.31%.计算得到煤矸石燃料比为0.88,综合燃烧特性指数S为32.34×10-11%2·min-2·K-3,说明试样挥发分析出速率快、极易着火燃烧、燃尽性能好,具有较高的自燃氧化及着火燃烧特性.%Spontaneous combustion of coal gangue ( CG ) causes serious environmental and ecological problems. The oxidation characteristics of coal gangue,such as mass loss rate,gas production rate and functional group change were studied using thermogravimetry-fourier transform infrared spectrometer ( TG-FTIR) technique and temperature programming experiment. FTIR spectrums indicated that coal gangue contained analogous hydroxyl, aliphatic, functional group, and aromatic compounds. Mean-while, the results showed that the total weight loss ratio of CG was about 30. 30% in the oxidation process;the CG spontaneous combustion process was divided into four phases,the weight loss at each stage was 1. 05%,3. 27%,20. 36%, and 5. 31%, respectively. The calculated fuel ratio of CG was 0. 88 and the integrated combustion characteristic index ( S ) was 32. 34 × 10 -11%2 · min-2 · K-3 ,which indicated that the sample of Wuhai CG has good oxidation and spontaneous combustion ignition property. The devolatilization rate is fast and the CG is easy to ignite.
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