【摘要】 火成岩侵入的煤层更易自然发火，这与岩浆对煤物理化学结构的改造密切相关，因此需探究火成岩侵入对煤体物化结构与低温氧化的内在影响机制.首先，基于氮气、二氧化碳等温吸附和傅里叶红外光谱测试研究了火成岩侵入区构造煤的孔隙结构和化学结构特征，岩浆的接触变质作用比热变质作用对煤体结构的改造程度更高；受接触变质作用影响煤样比表面积增涨了237.6%,其孔隙表面粗糙度和孔隙网络复杂度均升高，煤中芳香环、含氧官能团和脂肪烃含量降低，羟基和矿物含量升高，其化学结构特征参数均增大.其次，结合含瓦斯煤体程序升温试验与颗粒煤瓦斯外扩散数值模拟探究了甲烷与氧气的置换过程，结果显示岩浆的热变质作用强化了煤中甲烷与氧气的置换，但接触变质作用延缓了两者的置换；提出了一种定量计算煤物理吸氧量和化学吸氧量的新方法，并分析了煤中氧气的物理-化学吸附的转变过程，经历岩浆变质作用的煤样表现出较高的物理吸氧量，受热变质作用影响煤样的物理-化学吸附主控转变温度最低仅有55.22℃,降低了近20℃;基于阿伦尼乌斯公式和化学反应速率公式准确计算了煤-氧反应的表观活化能，热变质作用降低了煤-氧反应的表观活化能，而接触变质作用使表观活化能比正常煤样更高.最后，使用灰色关联分析探究了构造煤物化结构与其低温氧化的相关性，分析得到：构造煤孔隙表面粗糙度、孔隙网络复杂度以及支链化程度的提高，不仅促进了煤体内部甲烷与氧气的置换，使得低温氧化过程更快地由物理吸附主控转变为化学吸附主控，而且促使芳香烃断裂形成了更多长度更短的支链，致使煤与氧气反应的活化能降低，易于演变成强烈的氧化反应.更多还原

【Abstract】 Coal seams intruded by igneous rocks are more prone to spontaneous combustion, which is closely related to the physical and chemical structure modification of coal by magma, thus it is necessary to explore the intrinsic impact mechanisms of igneous rock intrusion on the physical and chemical structure and low-temperature oxidation of coal. First, based on nitrogen and carbon dioxide isothermal adsorption and Fourier infrared spectroscopy testing, the pore structure and chemical structure characteristics of tectonic coal in the igneous rock intrusion area were studied, and it was found that the contact metamorphism of magma is higher than the thermal metamorphism on the modification of the coal structure; the coal samples affected by the contact metamorphism had an increase of 237.6% in specific surface area, and both the surface roughness and network complexity of the pores increased, the content of aromatic rings, oxygen-containing functional groups, and alkanes in the coal decreased, while the content of hydroxyl groups and minerals increased, and the parameters of the chemical structure characteristics significantly increased. Secondly, the replacement process of methane and oxygen was investigated by combining programmed heating experiment of the gas-containing coal and the numerical simulation of gas diffusion in granular coal, and the results show that the thermal metamorphism of magma strengthens the replacement of methane and oxygen in the coal, but the contact metamorphism slows down the replacement of both. A new method for quantitative calculation of the physical and chemical oxygen absorption of coal was proposed, and the transformation process from physical to chemical adsorption of oxygen in the coal was analyzed, the coal samples subjected to magmatic metamorphism showed a higher physical oxygen absorption, and the main control transition temperature of physical-chemical adsorption of coal samples affected by thermal metamorphism was only 55.22 ℃, which reduced by almost 20 °C. The apparent activation energy of the coal-oxygen reaction was accurately calculated based on the Arrhenius formula and the chemical reaction rate formula, the thermal metamorphism reduced the apparent activation energy of the coal-oxygen reaction, while the contact metamorphism made the apparent activation energy higher than that of normal coal samples. Finally, the correlation between the physical and chemical structure of tectonic coal and its low-temperature oxidation was explored using gray correlation analysis, and it was found that the increase in the surface roughness, network complexity, and branching degree of the tectonic coal not only promoted the displacement of methane and oxygen inside the coal body, making the low-temperature oxidation process quickly shift from physical adsorption control to chemical adsorption control, but also promoted the breaking of aromatic hydrocarbons to form more short-chain branches, resulting in a reduction in the activation energy of the coal-oxygen reaction and easy evolution into a strong oxidation reaction.更多还原