为了研究不同变质程度烟煤的自燃特性变化，根据变质程度由低到高顺序，选用4种不同变质程度烟煤：宁夏灵武不黏煤、宁夏灵武气煤、山西霍州1/3焦煤以及辽宁沈阳瘦煤，分别开展液氮吸附实验、傅里叶红外光谱实验以及TG-DSC同步热分析实验。结果表明：随着变质程度的升高，烟煤的内部孔隙的比表面积逐渐增加，孔容积变化趋势与之相同；煤样中的活性官能团比重逐渐减小，化学性质相对稳定的官能团比重逐渐增加；烟煤的临界温度T₁与着火点温度T₄随着变质程度的加深而逐渐升高，煤样燃烧阶段的放热量逐渐减小。综上所述，随着变质程度的升高，烟煤化学性质趋于稳定，愈发难以自燃；煤样中的活性官能团的影响程度要比孔隙结构的影响程度要大。

In order to study the changes of spontaneous combustion characteristics of bituminous coal with different degrees of metamorphism, according to the order of metamorphism degrees from low to high, four types of bituminous coal with different degrees of metamorphism were selected: Ningxia Lingwu non-stick coal, Ningxia Lingwu gas coal, Shanxi Huozhou 1/3 coking coal and Liaoning Shenyang lean coal, and liquid nitrogen adsorption experiments, Fourier infrared spectroscopy experiments and TG-DSC simultaneous thermal analysis experiments were conducted respectively. The results showed that the specific surface area of internal pores of bituminous coal gradually increased with the increase of the degree of metamorphism, and the pore volume changed in the same trend; the proportion of active functional groups in coal samples gradually decreased, and the proportion of chemically stable functional groups gradually increased; the critical temperature T₁ and ignition point temperature T₄ of bituminous coal gradually increased with the increase of the degree of metamorphism, and the heat release in the combustion stage of coal samples gradually decreased. In summary, the chemical properties of bituminous coal become more stable with the increase of deterioration, and it is more difficult to spontaneously combust; the influence of active functional groups in coal samples is greater than that of pore structure.