Gas Drainage of Coal Mining Face in Tashan Mine Based on Micro Seismic Monitoring and Measuring Technology

In order to control the gas emission from the source point and to improve the gas drainage efficiency,a micro seismic monitoring and measuring technology was applied to monitor and measure the rack development in the roof strata above the coal mining face.The paper summarized the gas migration law of the surrounding rocks at the coal mining face and analyzed the gas accumulation and storage filed.The site observation found that the crack height in the roof strata above the No.8103 coal mining face in Tashan Mine was 75 m and this coal mining area was the source of the face gas emission.Thus this source should be sealed to stop the gas from above seam and the optimized layout location for the terminal end of the gas drainage borehole should be within 75 m from the roof.According to the gas accumulated area which was monitored and measured,the gas drainage borehole was designed to drain the gas from above seam and the average drainage value of the borehole designed was 0.64 m3/min.When the amount of the borehole drilling operation reached to 20 and the gas drainage value reached to 12.8 m3/min,the gas emission absolute value from the coal mining face would be reduced over 33%.