Application And Effect On The Methane Migration And Coal Spontaneous Combustion In Gob Induced By High Drainage Roaday

Mine gas and coal spontaneous combustion disaster constraint the mining efficient of working face, gas drainage in upper way is the effective method for governing methane in gob, but the leakage in gob will be changed, which can increase the possibility of coal spontaneous combustion in fully mechanized caving gob, so the effect of gas drainage in upper way on gas and coal spontaneous and determining the balance are important for coupling prevention of gas and coal fire in gob.Based on the fact of fully mechanized caving working face named 401102 with high gas emission and short spontaneous combustion period, the paper studies the effect of negative pressure on methane distribution and coal spontaneous, and the oxygen distribution equation in fully mechanized caving gob is set up, indicating that negative pressure is the main influence factor. Second, the paper carries out physical simulation experiment and obtains evolution rule of overlying strata. With mathematical model of rock porosity and permeability distribution established, it analysis the seepage properties in gob. The CFD numerical model and its boundary conditions are established by Ansys software, the paper gets the gas extraction effect and distribution characteristics of coal spontaneous three zones at different space layout position and extraction parameters. At last, it put forwards the method for parameters optimization and the suitable parameters are get which can satisfy the coupling prevention.The paper gets the distribution of the coal spontaneous three zones in gob according to the duct monitoring, and the methane distribution in the working face by field test in three dimensional space,at last, the paper conducts effectiveness evaluation of coupling hazard prevention of gas and coal fire, which the parameters can guarantees the safe mining of working face.