我国大部分煤层属于自燃、易自燃煤层，煤自燃火灾造成严重的环境污染和资源浪费，并严重威胁煤矿的安全生产。本论文采用实验分析和量子化学模拟的方法，针对不同变质程度煤样的氧化自燃过程，研究煤氧化自燃的微观特征与宏观表征特性，以进一步揭示煤自燃机理，对煤自燃预测和防治技术的研究具有重要的理论指导意义。 采用比表面积测定仪，X-射线衍射仪和煤自燃倾向性测定仪等，分析了煤质、比表面积和孔隙率与煤样变质程度间的关系，研究了煤的芳香微晶结构和煤物理吸氧特性随变质程度、氧化温度和煤样粒度的变化规律，得出煤芳香微晶结构的变化会导致煤宏观物理、化学特性的变化，以及表征煤氧物理吸附特性的活性时间和吸氧量与煤变质程度、温度和粒度的关系。 利用傅里叶变换红外光谱仪研究了不同条件下煤样的红外光谱特征，得出煤分子中官能团随煤变质程度、氧化温度和煤样粒度的变化规律，确定出煤分子中发生氧化反应的主要官能团及其氧化时的变化特征；并采用量子化学软件对主要活性基团分步氧化历程进行了模拟计算，分析了反应过程中的活化能及相关热力学和动力学参数，得出不同活性基团反应活化能、反应焓变的差异导致其对煤氧化自燃贡献的不同；证实了煤分子中桥键、侧链的活性较高，是煤氧化自燃的主要诱因，其中羧基是标志煤氧化的一个重要基团，一氧化碳是煤氧化自燃的主要宏观标志性气体，从微观角度上解释了煤分子微观结构的差异导致了不同煤样氧化自燃本质属性的不同。 根据油浴程序升温实验，研究了不同变质程度煤样氧化自燃的耗氧速率、气体产生速率、放热强度等宏观表征参数的变化规律，分析了煤样粒度对宏观表征参数的影响关系，通过对宏观表征参数的微观分析，研究了不同煤样宏观特性变化规律与其微观特征变化之间的对应关系，得出了煤氧化自燃宏观表征参数的微观解释。

A majority of coal seams in our country are prone to spontaneous combustion, which pollutes environment, deplete precious coal resource with no benefit and seriously threatens mining production. In this paper, experimental analysis and quantum chemistry simulation are conducted to study the process of oxidization of different rank of coal at lower temperature; the microcosmic properties and characteristic parameters of coal oxidized at low temperature are also studied to reveal mechanism of coal spontaneous combustion. The study is important in directing coal spontaneous combustion prediction and prevention technology research theoretically Using specific surface area analyzer, X-ray diffraction instrument and coal spontaneous combustion propensity testing instrument, the relation of coal composition, specific surface area and porosity to coal rank are studied. The law of coal physical adsorption of oxygen and aromatic microcrystalline structure varies with the rank, the progress of oxidation and the grain size of coal sample, which proved that the microcrystalline structure of coal largely determines physical, chemical properties of coal, as well as activation time and oxygen consumption which are used to characterize physical adsorption of coal. The law of variation of functional groups’ structure of different rank and particle size of coal sample during oxidation at different temperature is studied with FTIR. By means of quantum chemistry simulation of the main active groups’ stepwise oxidation progress, the activation energy, thermodynamics and kinetic parameters and enthalpy change of the process are obtained. The study reaffirmed that the high activation of side chains and bridge bond in coal microstructure are the major inducements of coal spontaneous combustion. The carboxyl group is a symbol of coal oxidation, and CO is a symbolic gas of coal spontaneous combustion. It proved from the microcosmic viewpoint that the differences of coal spontaneous combustion propensity are due to molecular micro-structure of different coal samples. According to the oil-bath programmed temperature oxidation experiments, some parameters characterizing coal spontaneous combustion including oxygen consumption rate, gas generation rate and exothermal intensity of different rank of coal is studied, and the impact of coal sample’s grain size on macroscopic characterization parameter is analyzed. By means of microstructure analysis and characteristic parameters study, the corresponding relation between the macro structure and the characteristic parameters of different coal sample is studied, and the characteristic parameters is explained in microscopic view.