富油煤是一种特殊的煤炭资源，集煤、油、气属性于一体，通过原位热解等方式可形成清洁燃料和化工原料，对缓解我国贫油状况具有重要意义。相较于含油煤，富油煤在微观上富含富氢结构，在宏观上的焦油产率在7%-12%之间，导致其在自燃过程中的氧化特性和活性结构存在差异。因此，针对富油煤自燃全过程开展深入研究至关重要。本文将理论分析、实验研究和数学方法相结合，系统研究了富油煤自燃过程中的宏微观特性，以及活性结构与自燃特性的构效关系。

选取了陕西地区红柳林与柠条塔煤矿煤样作为富油煤，陈家山与永红煤矿煤样作为含油煤；利用程序升温实验，研究了富油煤自燃过程中的气体释放规律、耗氧速率与放热强度，得到富油煤会释放更多的H₂等气体，同时具有更高的耗氧速率和更大的放热强度；基于TG实验，研究了富油煤自燃过程中的热失重变化，划分了失水失重、动态平衡、吸氧增重与燃烧失重四个阶段，明确了自燃过程中特征温度及燃烧特性参数等规律；通过KAS法计算了富油煤自燃过程四个阶段的动力学参数，并利用FWO法进行验证，得出富油煤在失水失重、动态平衡与燃烧失重三个阶段的活化能均低于含油煤，在吸氧增重阶段的活化能高于含油煤；利用DSC实验，分析了富油煤在自燃过程中的特征温度点与放热规律，划分了失水、氧化与燃烧三个阶段，表征了自燃过程中三个阶段的热效应特征与吸放热的变化规律；采用原位漫反射傅里叶红外光谱仪，测试了富油煤自燃过程中的主要官能团变化规律，明确了常温下富油煤的结构特征，确定了自燃过程中主要活性基团的变化规律。

基于多重共线性基础理论，以15种微观结构特征为自变量X，以活化能为因变量Y。通过Pearson相关系数与VIF值对微观结构特征之间的多重共线性进行诊断，筛选出在失水失重、动态平衡、吸氧增重与燃烧失重四个阶段内的主要微观结构特征。在此基础上，采用逐步回归与岭回归模型，建立了自变量X与因变量Y之间在各阶段内的构效关系。所得模型在统计学上均表现出有效性与可靠性，通过相对误差值筛选出了各个阶段的最优模型，并利用方程系数筛选出各个阶段的关键微观结构。结果显示，岭回归模型能更准确地表征富油煤的构效关系，同时游离氢键、甲基与亚甲基等富氢结构在整个自燃过程中起重要作用。该模型具有一定解释富油煤自燃危险性的能力，为未来深入研究和测定富油煤提供了有力依据。

Oil-rich coal is a special coal resource that combines the properties of coal, oil, and gas. It can form clean fuels and chemical raw materials through in-situ pyrolysis and other methods, which is of great significance to alleviating my country's oil-poor situation. Compared with oil-bearing coal, oil-rich coal is rich in hydrogen-rich structures at the microscopic level, and the tar yield at the macroscopic level is between 7% and 12%, which leads to differences in its oxidation characteristics and active structures during the spontaneous combustion process. Therefore, it is very important to conduct in-depth research on the entire process of spontaneous combustion of oil-rich coal. This paper combines theoretical analysis, experimental research and mathematical methods to systematically study the macroscopic and microscopic characteristics of oil-rich coal during spontaneous combustion, as well as the structure-activity relationship between active structure and spontaneous combustion characteristics.

Coal samples from the Hongliulin and Ningtiaota coal mines in Shaanxi were chosen as oil-rich coal, while samples from Chenjiashan and Yonghong coal mines were selected as oil-bearing coals. Through programmed temperature experiments, the gas release patterns and oxygen consumption during the spontaneous combustion of oil-rich coals were investigated. It was observed that oil-rich coal releases more gases such as H₂ and exhibits a higher oxygen consumption rate and greater heat release intensity. Based on TG experiments, the thermal weight loss of oil-rich coal during the spontaneous combustion process was examined, revealing four stages: water loss, dynamic equilibrium, oxygen absorption weight gain, and combustion weight loss. The characteristic temperature and combustion parameters during the spontaneous combustion process were elucidated. The KAS method was employed to calculate kinetic parameters for the four stages of the spontaneous combustion process of oil-rich coal, which were verified by the FWO method. It was concluded that the activation energy of oil-rich coal in the stages of water loss, dynamic equilibrium, and combustion weight loss is lower than that of oil-bearing coal, while it is higher in the oxygen absorption and weight gain stage. Utilizing DSC experiments, characteristic temperature points and heat release patterns of oil-rich coal during spontaneous combustion were analyzed, dividing the process into three stages: water loss, oxidation, and combustion. The thermal effect characteristics and absorption/release patterns during these stages were characterized. Lastly, an in-situ diffuse reflection Fourier transform infrared spectrometer was employed to examine the change in main functional groups during the spontaneous combustion process of oil-rich coal, clarifying the structural characteristics of oil-rich coal at room temperature and identifying the changing patterns of main active groups during spontaneous combustion.

Based on the theory of multicollinearity, 15 microstructural characteristics are used as the independent variable X and the activation energy is used as the dependent variable Y. The multicollinearity between microstructural features was diagnosed through Pearson correlation coefficient and VIF value, and the main microstructural features in the four stages of water loss and weight loss, dynamic equilibrium, oxygen absorption weight gain and combustion weight loss were screened out. On this basis, stepwise regression and ridge regression models were used to establish the structure-activity relationship between the independent variable X and the dependent variable Y in each stage. The obtained models all showed statistical validity and reliability. The optimal models at each stage were screened out through relative error values, and the key microstructures at each stage were screened out using equation coefficients. The results show that the ridge regression model can more accurately characterize the structure-activity relationship of oil-rich coal. At the same time, hydrogen-rich structures such as free hydrogen bonds, methyl groups and methylene groups play an important role in the entire spontaneous combustion process.The model has a certain ability to explain the spontaneous combustion risk of oil-rich coal, and provides a strong basis for future in-depth research and measurement of oil-rich coal.

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