Abstract:
Coal is a complex natural porous solid substance and its nano-scale pore has a significant impact on the stor- age and migration of coalbed methane. Influenced by multi-stage tectonic movements in coal-forming basins in China, different types of deformed coal are widely developed in coal seams,and the nano-pore structure changes greatly under the action of tectonic deformation. This change not only affects the state of gas reservoir and occurrence in coal seams, but also has a significant impact on coal and gas outburst prediction and coalbed methane extraction. Samples of de- formed coal with different deformation degrees in Shoushan No. 1 and Yi’an Mines were collected. Based on the exper- iments of low temperature liquid nitrogen adsorption (2-50 nm) and carbon dioxide adsorption (