Study on Marked Gas of Spontaneous Combustion and Forecasting Index System Under Coal and Oil Shale Mining Conditions

In view of the problem of the index gas preference in the spontaneous combustion of the goaf under the conditions of coal and oil shale mining in Liangjia Coal Mine, the sample from 1105 working face was selected to simulate the natural gas content of coal and oil shale using a temperature programing experiment. The generation laws of CO, olefins, alkanes and their ratios were analyzed, and the forecasting technology of coal and oil shale spontaneous combustion was studied. The results show that the critical temperature of CO is around 40 ℃, and this marked the beginning of a reaction of coal and oil shale; C₂H₄ appears at about 120 ℃, indicating that the coal and oil shale had entered the stage of accelerated oxidation; C₂H₄/C₂H₆, C₂H₄/C₃H₈ can be used as the auxiliary gases for predicting the spontaneous combustion of coal and oil shale. At the same time, according to the gas release amount of CO, C₂H₄, etc, the identification parameters for the spontaneous combustion of coal and oil shale in Liangjia Coal Mine were determined.