Optimum oxidation temperature of coal bed for methane desorption in the process of CBM extraction

To explore the optimum oxidation temperature of coalbed for promoting methane desorption, this paper carried out the experiments based on the self-built coal oxidation heating system in different gaseous environments and the high-temperature and high-pressure gas adsorption instrument. Besides, the effect of methane on free radicals and surface functional groups at the optimum oxidation temperature was studied by using electron spin resonance (ESR) spectrum and Fourier transform infrared spectroscopy (FTIR). The results show that the residual methane is the lowest at the oxidation temperature of 80 °C, indicating that 80 °C is the optimum oxidation temperature for CBM extraction. At 80 °C, the inhibitory effect of methane on the reactivity of coal is stronger and the reactivity can also increase. At low concentration (