Abstract:
For the single low permeability soft coal seam, an improved experiment on technology of fracturing roof was performed. It can improve the ability of permeability by using hydraulic fracture in the roof. The physical simulation experiment for roof hydraulic fracturing virtual reservoir was carried out by multi-field coupling of coalbed methane exploitation system in this paper. The experimental results show that: it can better monitoring hydraulic fracturing fissures through the water pressure sensor in the roof and coal seam; the hydraulic fracturing of the virtual reservoir on the roof has the effect of releasing the gas pressure on the coal seam, on the other hand, the fracturing cracks spread along the borehole toward the coal seam and forms the cracks network. The coal seam gas can be extended through fissures network to the floor virtual reservoir drilling, which can effectively increase gas seepage channel and the gas extraction efficiency.