The effect of power sound wave on storage and motion of coalbed methane

The rules and effect of power sound wave (PSW) on porosity and permeation of coal or rock were analyzed.The results show that PSW can increase pore volume of coal and can enhance permeability of coalbed methane (CBM) in coal. The main mechanism of PSW acting on coal or rock is mechanical action, shock wave action, directional action, heat effect and acoustic cavitation. These effects can make coal seam produce micro-crack, change porous structure of coal and decrease viscidity of methane. The research can provide a new thinking for the exploitation and development of CBM.