College of Safety Science and Engineering, Xi’an University of Science and Technology

煤自燃灾害严重威胁了矿井的安全生产,掌握煤自燃微观基团和特征温度之间的关联性对煤自燃灾害的防治具有积极作用。为确定不同变质程度煤自燃过程中特征温度和煤微观结构的变化及相互联系,利用热重试验和傅里叶红外光谱实验分别测试了 4 种不同变质程度煤样自燃过程中的质量变化特性和微观结构,采用皮尔逊相关系数法确定了 2 者之间的联系。结果表明:随着变质程度的增大,煤中的芳香烃和脂肪烃含量增加,含氧官能团含量减少,3 种类型的基团中含量最高的基团分别为 C=C,—CH3 和—OH。变质程度高的煤失重曲线和特征温度逐渐向高温区移动,且各特征温度间的间距增大。煤自燃特征温度会随着芳香烃含量的增加而增加,随着含氧官能团含量的增加而降低。芳香烃含量越大,煤自燃越难发生,而含氧官能团则恰好相反。皮尔逊相关系数计算结果表明,随着温度的升高,正相关系数最大的官能团分别为 C—H,C—H,C—H,取代苯,C=C 和C=C,负相关最大的官能团分别为 COO—,COO—,C—O—,COO—,—OH 和—OH。整体而言,C—H 与特征温度之间正向相关性最大,而 COO—则与特征温度呈最大的负相关。特征温度的变化与最大官能团的含量呈较为明显的线性关系。基于皮尔逊相关系数的结果,利用与特征温度相关性最大的 C—H 和 COO—官能团的含量建立了煤自燃倾向性多元线性回归模型。

The coal spontaneous combustion disaster seriously threatens the mine safety production. Mastering the correlation between themicro group and characteristic temperature of coal spontaneous combustion plays a positive role in the prevention and control of coal spontaneous combustion disaster. In order to determine the change and correlation of characteristic temperature and coal microstructure in theprocess of spontaneous combustion of coal with different metamorphic degrees, the mass change characteristics and microstructure of fourcoal samples with different metamorphic degrees were tested by thermogravimetric experiment and Fourier infrared spectrum experiment,and the relationship between them was determined by Pearson correlation coefficient method. The results show that with the increase ofmetamorphic degree, the content of aromatic hydrocarbons and aliphatic hydrocarbons in coal increases and the content of oxygen-containing functional groups decreases. The groups with the highest content in the three types of groups are C=C, —CH3 and —OH respectively.The weight loss curve and characteristic temperature of high metamorphic coal gradually move to the high temperature zone, and the spacing between characteristic temperatures increases. The characteristic temperature of coal spontaneous combustion increases with the increase of aromatic hydrocarbon content and decreases with the increase of oxygen-containing functional group content. The higher thecontent of aromatic hydrocarbons, the more difficult coal spontaneous combustion is, while the oxygen-containing functional groups arejust the opposite. The calculation results of Pearson correlation coefficient show that with the increase of temperature, the functionalgroups with the largest positive correlation coefficient are C—H, C—H, C—H, substituted benzene, C=C and C=C, and the functionalgroups with the largest negative correlation are COO—, COO—, C—O—, COO—, oh and —Oh, respectively. On the whole, C—H hasthe greatest positive correlation with the characteristic temperature, while COO— has the greatest negative correlation with the characteristic temperature. The change of characteristic temperature has an obvious linear relationship with the content of the maximum functionalgroup. Based on the results of Pearson correlation coefficient, a multiple linear regression model of coal spontaneous combustion tendencyis established by using the contents of C—H and coo functional groups which have the greatest correlation with characteristic temperature.

国家自然科学基金资助项目(51974235,51774233)

张玉涛, 杨杰, 李亚清, 等. 煤自燃特征温度与微观结构变化及关联性分析[J]. 煤炭科学技术, 2023, 51(4): 80-87.

ZHANG Yutao, YANG Jie, LI Yaqing. Correlation analysis between characteristic temperature and microstructure of coal spontaneouscombustion[J]. Coal Science and Technology, 2023, 51(4): 80-87.