The Experiment And Study On The Gas Drainage By High Level Boreholes In Shuilian Coal Mine

In fully mechanized caving face of high gassy and ultra thick seam, much residual coal leave in its goaf. affected by roof stratum caving, the condition of the gas from adjacent seams pouring into the goaf is very common. It makes the gas emission quantity from the goaf keeping in high level, the gas overrun in the upper corner seriously restrict the normal production activities. On the base of summarizing methods of methane harness in goaf and upper corner. Analyzing roof stratum broken moving rule and gas flow resistance distribution, putting forward based on the goaf "three zone" division and "O—X" type of roof stratum breakage, the technical feasibility of draining the clustering gas on the top of goaf by high level boreholes. After determining the best drainage zone, taking advantage of physical model established by similar material, reappear and analyze the influence of the gas drainage effect in the process of rock falling. At the same time, using RFPA analysis software simulating and speculating falling range of mining roof stratum as well as "three zone" distribution, calculating the roughly height of longitudinal "three zone" in the goaf, after comparing the similar simulation and computer simulation data, determining reasonable parameters interval of high level borehole drainage. Finally, in Shuilian 8 coal seam mining face, through constructing high level boreholes, continuously observing flow changes, verifying the reliability of these parameters further, improved the reliability of drainage design parameters, and provided the scientific reliable test basis for large-scaled applying this technology in coal mine and guarantee for 8 coal seam mining safely and efficiently.Figure [49] Table [7] Reference [52]...