Research On Hydraulic Fracturing Technology Of11313Working Face Of A3of Panbei Mine Coal Seam

This article mainly discusses the research on hydraulic fracturing to relief pressure and anti-reflection technology of panbei coal mine,and use the method of combining with numerical simulation, theoretical analysis and field test, and use A311313working face of coal seam floor lane area of field as experiment to study the effect of hydraulic fracturing. The results show that hydraulic fracturing can improve the permeability of A3coal seam, increase the radius and rate of extraction in order to lower the coal seam outburst danger.this paper talk from mechanics theory, numerical simulation and field experiments this three aspects to research and analysis in hydraulic fracturing anti-reflection layer drilling technologies for low gas permeability of coal seam.Analyzed the wear layer crack borehole fissure water fracturing pressure and the crack location from the point of view of mechanics:only under the condition of considering the radial horizontal stress, crack pressure for pH1(\+Ac)qo+2(\-Ac)qocos20+mm{R,l}; Only under the condition of considering the axial horizontal stress,crack stress is Pm=q0cosa+Apq0sma+mm{cl}. Therefore pH=mm{pm,pH2}, at the time pH=pH2, fracturing borehole water injection will along a certain direction of bedding face normals crack, crack in the weakest bedding surface location. At that time pn=pm, the crack location is determined by min{.R,,} and Xc, at the time including crack under the action of water pressure drilling q0position is located in the section on the horizontal direction of the weakest coal crack along the vertical direction; At that time the crack in the period of the weakest coal on the vertical direction of crack along the horizontal direction.Through RFPA2D-Flow numerical simulation software, I can explore the buried depth of coal seam and the hydraulic fracturing on the relationship between the crack and the influence of coal seam gas pressure of hydraulic fracturing test, it is concluded that crack coal and rock pressure increases with depth of coal seam. Micro crack, based on the relationship between pressure and buried depth is n=74014e00014’’’tne correlation coefficient is0.9754; Based on the relationship between fracture pressure and buried depth is p=6.5764e0.0018h, the correlation coefficient is0.9662; Coal seam gas pressure will cut the effect of hydraulic fracturing of high pressure water injection, offset some of the water injection pressure.The greater the gas pressure of coal the more difficult it is to break.In the implementation of hydraulic fracturing technology, it is important to increasing injection pressure when gas mine hydraulic fracturing to achieve expected effect.The experiment of hydraulic fracturing at11313floor of panbei mine lane, through the contrast of the radius of the moisture content before and after hydraulic fracturing, and extraction effect, concluded that hydraulic fracturing effective radius is20m; The effective radius of extraction by fracturing increase2.5m to6m; After fracturing, the gas extraction from scalar in the peak district average increased by6.42times, compared with the original fracturing gas extraction from scalar. The gas extraction from scalar stabilized average increased by2.16times, compared with the original fracturing gas extraction from scalar.Technology research on pressure relief and anti-reflection within the A3of panbei mine coal layer, combining with the field measurement, it is verified the accuracy of the mechanics analysis result and the numerical simulation results.