压降法在瓦斯抽采钻孔有效抽采半径的应用研究

Application of pressure drop method to effective extraction radius of gas extraction drilling

钻孔抽采瓦斯是防治煤矿瓦斯事故的重要手段,钻孔间距的合理布置直接影响钻孔瓦斯的抽采效果。以山西潞安环保能源开发股份有限公司常村煤矿2106工作面为试验地点,采用压降法测定普通顺层钻孔及酸化压裂钻孔的有效抽采半径。现场试验表明:随着抽采时间的延长钻孔瓦斯压力持续减小,被测孔与测压孔的间距越大,钻孔达标所需要的抽采时间越长。顺层钻孔抽采时间90 d时其有效抽采半径为3 m,当酸化压裂钻孔抽采时间为90 d时其抽采钻孔有效抽采半径为6 m。

Gas extraction by drilling is an important means of preventing and controlling gas accidents in coal mines,and the reasonable arrangement of drilling spacing directly affects the effect of gas extraction by drilling.Taking the No.2106 working face of Changcun Coal Mine of Shanxi Lu′an Environmental Protection Energy Development Co.,Ltd.as the experimental site,the effective extraction radius of ordinary bedding layer drilling and acid fracturing drilling were determined by pressure drop method.The field test showed that with the extension of the extraction time,the gas pressure of the drilling decreased continuously,and the larger the distance between the measured hole and the pressure measurement hole is,the longer the extraction time required for the drilling to reach the standard was.When the extraction time of the bedding layer was 90 days,the effective extraction radius of the drilling was 3 meters.When the extraction time of the acid fracturing drilling was 90 days,the effective extraction radius of the drilling was 6 meters.The effective extraction radius of the bedding drilling is 3 m when the extraction time is 90 days,and the effective extraction radius of the acid fracturing drill hole is 6 m when the extraction time is 90 days.