Research On Permeability Increased Range Of Hydraulic Fracturing In Pan Ⅱ Coal Mine

This study of the pan II mine hydraulic fracturing pressure and the range permeability increased systematically from two aspects: the coal seam depth and protodyakonov coefficient using theoretical analysis, numerical analysis and field test a combination of methods, based on the exist research results. The paper obtained the following beneficial results:(1) According to the historical data and field testing parameters of pan II mine, this paper analyzed the gas pressure, the gas content and permeability etc. characteristics and laws.(2) Based on the pore structure of coal and hydraulic fracturing breakdown criteria, this text analyzed the fracture mode in hydraulic fracturing and the enhancing permeability principle of hydraulic fracturing.(3) Based on the data tested in Pan II mine 3 coal seam field of Huainan Mine Group, we uses RFPA2D numerical software to analysis two parameters in hydraulic fracturing: fracture pressure and increased range of the permeability, in different depth and sturdiness coefficient. According to the numerical calculation results, by analysis the relationship fracture pressure among the buried depth and sturdiness coefficient, we ascertain the increased range of the permeability in different buried depth and sturdiness coefficient, also get the fracture pressure and reasonable range of water pressure of hydraulic fracturing.(4) In order to solve the current difficult problem sealing in high pressure, this article discussed a technique about drainage hole sealing and sealing of hydraulic fracturing special sealing device. And according to the tests of range permeability increased by hydraulic fracturing, obtained radius of influence in Panâ…¡coal mine.