Experimental Study On Mechanism Of Coal Spontaneous Combustion Induced By Active Groups In Coal

In view of the problem of spontaneous combustion of coal,it is of great significance to study the natural ignition of coal by combining theoretical analysis and laboratory experiments to carry out scientific research on spontaneous combustion induced by active groups.The following major research results have been obtained:By selecting five kinds of coal samples with different degrees of metamorphism,the deashing treatment was carried out,and the infrared spectroscopy analysis and XPS experimental analysis were carried out on the deashed coal samples,and the types of functional groups（C-H）and active groups containing N,O,S and other active groups in coal were obtained,and the content of different hydrocarbon functional groups was quantified by the standard working curve of infrared spectroscopy internal standard method,and the molar mass of active groups containing N,O,S and other active groups was calculated by elemental analysis.The oxidation heating rate and natural ignition period of coal samples were obtained by adiabatic oxidation experiment,and it was found that the oxidation heating rate of deashed coal was V_{LA T}>V_{LJH T}>V_{NM T}>V_{TS T}>V_{HJ T}.The TG-DSC curve was obtained by the programmed heating experiment,and the characteristic temperature point and heat release were obtained from the TG-DSC curve.There are 36 pictures,22 tables and 70 references in the dissertation.Through analyzing the effect of the content of C-H active groups on the oxidation heating rate of coal samples,it is found that the contents of symmetric-CH₃ and antisymmetric-CH₂ in C-H active groups increased from 0.01 and 0.05 to 0.42 and 0.75,respectively,while the low-temperature oxidation heating rate of coal samples decreased from 1.8°C/h to 0.8°C/h.The activities of hydrocarbon functional groups linked by different structures are different.Similarly,in the DSC curve,the content of C-H active groups was negatively correlated with the exothermic heat.Secondly,it was found that the content of oxygen-containing functional group（C-O）was consistent with the low-temperature oxidation heating rate of coal,the C-O content decreased from 0.18g/mol to 0.05g/mol,and the low-temperature oxidation heating rate of coal showed a positive correlation with the（C-O）content,which was positively correlated with the oxidative heat release and combustion heat release of coal samples.It is of great significance to study the intrinsic occurrence law of the type and content of active groups in coal,which is of great significance for analyzing the spontaneous combustion mechanism of coal induced by active groups.There are 36 pictures,22 tables and 70 references in the dissertation.