Research On High Drill Holes For Release-methanes Drainage With Wu Hushan Colliery

Coal is the staple energy in our national economic development, And gas disaster have been affecting the overall situation of our country’s safety in production for many consecutive years, Relief-pressure gas drainage is an important channel of the coalbed strata gas control, which can help greatly improve conditions of coal work safety、enhance the economy efficiency of mine the safe and realize high-efficient exploitation of coal and gas.Researches and applications on migration theories with coal excavation and methane control technologies with high drill holes have been reviewed systematically. No.1201fully mechanized working face from Wuhushan colliery was consideration as study area here. With general mining and geological settings, basic mechanical parameters on rock masses were clearly gotten from inner-testings. Next elastic-plastic model which was applied for mechanism between crack field after coal excavation and rock mass stress and stess features in rock-fracture space with ANSYS numerical simulation software. Surely fracture and fissure zone in the study area should be estimated obviously. Secondly, based on theoretical analysis, another numerical simulation software, FLUENT, mainly was used to simulated distribution of methane concentration in period of coal seam group excavation, and the influence on gas concentration distribution in goaf with tail entry drainage or not.Methane control schemes with high drill holes in period of coal excavation were used to in-situ industrial experiments based on simulation results with consideration to source analysis and prediction of methane emission. It fully took into account about drainage quantity of mono-drill hole with excavation distance, and drainage time, and ultimately determined the reasonable parameters for high drill holes.Finally, drainage parameters from both numerical simulations were effective for methane drainage design. High drill hole being in fracture-fissure zone was advantage to achieve better drainage effects and provide safe and efficient coal excavation. All above points would offer theortical and technological supports for release-methane extraction optimization and simultaneous excavation of coal and methane.