Research On Gas Explosion Dangerous Area In Goaf Of High Gas Working Face

With the continuous increase of mining depth,the phenomenon of gas explosion caused by spontaneous combustion of coal in goaf is more widespread,which brings great potential for coal mine safety production.In this paper,taking the goaf of 2201 working face in the Tai Yue coal mine as the research object,through theoretical analysis and numerical simulation,the law of gas migration in the goaf of high gas working face and the dangerous area of gas explosion in the goaf are studied,which provides the basis for the prevention and control of the mine gas disaster.From the conditions of coal spontaneous combustion in the goaf,combined with the range of gas explosion concentration,it is considered that the oxygen concentration in the goaf is 12%?18%,and the gas concentration 5%?16%is the main condition of gas explosion in goaf caused by spontaneous combustion of coal in the goaf.The simulation of 2201 working face partial W ventilation system is carried out,and the effect of partial W ventilation system on gas control in working face is analyzed.The distribution of pressure and gas concentration field of U ventilation system is simulated by different advancing distance and different air volume at working face.When the working face has different propelling distance,the gas explosion range is mainly concentrated in the range of 50 meters to 70 meters in the rear of the working face.When the working face is pushed to 130 meters,the gas explosion range of the inlet side is larger than that of advancing to 80 meters and 180 meters.In the middle of the working face,when the working face is pushed to 80 meters,the range of gas explosion in the goaf is larger than that of 130 meters and 180 meters,while the gas explosion range in the goaf on the return air side of the working face is relatively small.When the air volume of the working face is different,the area of gas explosion prone to the goaf in the middle of the working face to the middle of the working face is smaller,mainly concentrated in the goaf from 70 to 90 meters from the working face.With the change of the air volume in the working face,the area of gas explosion prone area is less affected.In the wind return section of the working face,it is about 120 meters to 160 meters in the working face.With the increase of the air volume at the working face,the extent of gas explosion in the area is relatively small.According to the numerical simulation results,with 2201 fully mechanized working face of coal mine as engineering Taiyue test conditions,field practice research.