Study on the characteristics of coal and gas outburst hazard under the influence of high formation temperature in deep mines

Coal and gas outburst is a type of disaster whose hazard intensifies increase with the formation temperature. In this study, the impact of temperature (10–50 °C) on gas “energy-mass” characteristics was investigated, and the indexes for outburst hazard prediction were improved. Results shown that, temperature has varying influences on gas release parameters, and the influence laws are obviously different under the conditions of the same pressure and the same gas content. Taken the initial expansion energy of released gas (IEERG) as the criterion of outburst hazard, under the same gas content, IEERG changes exponentially with temperature (R2 = 0.9924); under the same gas pressure, IEERG changes as a power function with temperature (R2 = 0.7). The variation coefficients of the influence of temperature change on IEERG under the same gas content and the same pressure are 0.1612 and 0.01489 respectively, indicating the gas content index is more sensitive to temperature. This study also proposed a method to re-evaluate the critical value of the prediction index of coal seam outburst hazard in deep high-temperature mines. This method is expected to provide a solution for the safe mining of deep coal resources.