Determination of the gas drainage radius of low permeability and high gas coal seam by SF₆ gas tracer

Aiming at the problem that the relative gas pressure determination can not accurate determine the gas drainage radius, this paper takes the 16# coal seam in Pinggou coal mine of Wuhai Shenhua Energy Company as the research object.16# coal seam is of low permeability and high gas content. Boreholes for gas drainage test were drilled in the working face 1606, and SF₆ gas tracer method was used to determine the gas drainage radius, Then the drainage effect of different radius in field test was compaired. The test results showed that the gas drainage radius tested from SF₆ gas tracer method can obviously improve the extraction efficiency.This method provided a basis for the design of gas drainage borehole spacing for the coal seam, and can be used to determine gas drainage radius in the coal seam of low permeability and high gas content.