特厚煤层综放工作面瓦斯抽采技术研究

为解决蒋家河煤矿采空区瓦斯涌出量大、上隅角瓦斯超限和回风平巷风排瓦斯量大等问题,提出了本煤层预抽、专用瓦斯抽放巷抽采和上隅角埋管抽采瓦斯相结合的方法对该矿ZF202综放工作面进行瓦斯治理,进行了现场实测和瓦斯抽采效果分析。结果表明,本煤层预抽后,瓦斯含量由7.92 m^3/t下降为4.21 m^3/t,瓦斯压力由0.72 MPa下降为0.38 MPa;上隅角瓦斯浓度由0.78%下降至0.4%左右。通过对比,专用瓦斯抽放巷的抽采纯量是高位钻孔的2.5倍,抽采效果好于高位钻孔,使工作面和上隅角瓦斯浓度保持较低水平,有效地解决了特厚煤层综放工作面瓦斯超限问题,为安全生产提供了重要保障。

Research on Comprehensive Gas Extraction Technology of Fully Mechanized Caving Face in Extra Thick Coal Seam

In order to overcome the difficult problems associated with large gas liberation in goaf of Jiangjiahe coal mine,upper corner to solve gas concentration exceeding limits and large gas liberation in air-return way,proposed comprehensive control measures of gas,which is coal seam pre-extraction,the extraction of special gas extraction roadway and the extraction of buried pipe on the upper corner to make gas comprehensive control for ZF202 fully mechanized caving face in Jiangjiahe coal mine,and measure and collect date on the spot.Thus analyses gas extraction effect of the coal mine.The results show that after coal seam pre-extraction,the gas content of coal seam reduces from 7.92 m^3/t to 4.21 m^3/t;the gas pressure of coal seam reduces from 0.72 MPa to 0.38 MPa;gas concentration in upper corner decreased from 0.78%to about 0.4%.By contrast,gas quantity of special gas extraction roadway is 2.5 times as high level borehole.Pumping effect of special gas extraction roadway is better than high hole drilling,which remains the gas concentration in working face and the upper corner low.This method can effectively solve the problem of gas overrun in the fully mechanized caving face with extra thick coal seam and ensure the safety of production.