Inhibitory Effect of Low Temperature on Methane Diffusion in Coal

For the problem that coal seam gas content measurement values are not accurate due to the high temperature of coal samples and excessive gas emission volume causing value deviation of losses during the determination of gas content in underground coal seam, based on the characters that gas emission rate of coal increases with the increasing of temperature, low temperature (below 0 ℃) sampling of coal is proposed in order to suppress gas emission and improve the accuracy of coal seam gas content determination values. The results showed that low temperature sampling can increase methane adsorption in coal, slow down gas emission rate especially in the beginning period and suppress gas desorption.