Exploration on Enhancing Extraction of CBM in Water-sensitive Reservoir by Combustion of Coal Seams

The conventional way to exploit coalbed methane is pressure lowering through drainage, which means that reducing pressure through water drainage for coalbed methane desorption. While, for water-sensitive reservoir, the recovery by conventional way is low; in order to exploit water-sensitive reservoir, combustion of coal seam is proposed to increase recovery ratio, and then theoretical feasibility is elaborated through four aspects: improving activity of molecules by temperature, diffusion by pressure, migration path by superficial area, promoting adsorption and desorption by competition; then given an example of water-sensitive reservoir, the obtained results show that the recovery is effectively improved through combustion of coal seam.