SF_6气体示踪法测定低透气性高瓦斯煤层瓦斯抽放半径

Determination of the gas drainage radius of low permeability and high gas coal seam by SF_6 gas tracer

针对目前应用较多的瓦斯抽放半径测定方法——相对瓦斯压力测定法与实际情况偏差较大问题,以神华乌海能源公司平沟煤矿16号低透气性高瓦斯煤层为研究对象,在井下1606工作面施工瓦斯抽放试验钻孔,采用SF6气体示踪法测定工作面瓦斯的抽放半径,并比较了不同抽放半径的瓦斯抽放效果。实测结果表明,SF6气体示踪法所测定的瓦斯抽放半径使瓦斯抽采效率显著提高,该方法为煤层预抽瓦斯钻孔间距的设计提供了依据,可以在低透气性高瓦斯煤层的瓦斯抽放半径测定中推广使用。

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 SF6gastracer 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 SF6gastracer 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.