The first-appearance temperatures of C 2H 2 were 180☌ and 195☌ for the HQL and DY coals, respectively. The indicator gas detection results showed that the first-appearance temperature of C 2H 4 was 85☌ for the HQL and DY coals, whereas the first-appearance temperature of C 2H 6 varied: 115☌ for the HQL coal and 130☌ for the DY coal. The results of the thermogravimetric analysis experiment showed that the pyrolysis temperatures of the HQL and DY coals were 115.76☌ and 131.80☌, and the ignition temperatures were 337.74☌ and 360.18☌, respectively. In this study, the characteristic temperature of coal spontaneous combustion, the generation law of indicator gases, the combustion process, and the division of the combustion stages of coal samples taken from Hongqingliang (HQL) and Dayan (DY) mines were investigated using thermogravimetric analysis experiment, indicator gas detection experiment, and coal oxidation spontaneous combustion experiment.
Investigating the division of coal spontaneous combustion stages and the selection of indicator gases is significant to the safe production of coal mines.
