Research on index gas and activation energy of coal spontaneous combustion under different methane atmosphere

Most researches on coal spontaneous combustion characteristics under different oxygen concentration only consider different oxygen nitrogen ratio atmosphere, but low temperature oxidation law of coal under different methane atmospheres is seldom studied. In view of the above problems, index gas and activation energy of coal spontaneous combustion under different methane atmospheres were researched by temperature-programmed oxidation experiment and thermogravimetric analysis experiment. The results show that initial temperature of CO and CO2 production increase significantly with the increase of methane volume fraction. In initial stage of coal oxidation, production quantity of CO and CO2 under different methane atmospheres increase slowly with the increase of temperature. In accelerated oxidation stage of coal, production quantity of CO and CO2 increase exponentially with the increase of temperature, and the lower the methane volume fraction (the higher the O2 volume fraction) is, the larger the production quantity of CO and CO2 is, indicating that the higher the temperature is, the more obvious the inhibition effect of methane on coal oxidation is. With the increase of methane volume fraction, oxidation activation energy of coal at low temperature increases and index factor decreases, indicating that the increase of methane volume fraction has a good inhibition effect on coal spontaneous combustion.