Study On Cubic Gas Drainage Technology For Low Permeability Coal Seam In Pingdingshan No.10 Coal Mine

Mine gas problem is a serious threat to China's coal mine safety production,gas drainage is one of the most important way to solve the mine gas accident,How to efficiently and safely exploit the gas of coal seam is a continuous research.In view of the fact of low permeability and high gas emission in the F15-24080 coal face in.The basic parameters of coal seam are measured by field and laboratory methods,get the gas content is coal seam is characterized by high content,high pressure and low permeability.Use different-source forecast method to predict the gas emission in the working face is predicted to determine the main source and the gushing amount.According to the working characteristics of low permeability is difficult to drainage and combining live production practice,determine the crossing hole at floor roadway,drilling long borehole down the seam,coal mining face shallow hole drilling,upper corner pipe,highly-located drainage road way comprehensive cubic drainage technology to solve the gas problem.Based on the theory of gas percolation and the field and field test data,Through COMSOL software numerical simulation,confirmed the negative pressure of the mining method by-25KPa,the drilling distance is 3m,the length of the mining pipe is 80m,the mining angle is 15°,see the coal poiint spacing 3m;mining face shallow hole drilling spacing of 3 m when the best extraction effect.Establish a standard system of gas drainage on spot investigation of mining effect,The results showed that the maximum amount of drilling debris was 3.61kg/min,the initial velocity of borehole gas was 2.67L/min,the residual gas content,the maximum gas pressure is 0.548MPa,the gas extraction rate of the coal face is 37.22%,the maximum gas concentration in the coal face is 0.35%,and the extraction scheme meets the requirements of the pumping standard.