沙区矿保护层卸压瓦斯抽采技术研究

Research on Pressure Relief Gas Extraction Technology of Protective Seam in Shaqu Coal Mine

为防治沙区矿近距离煤层群瓦斯,研究了保护层卸压瓦斯运移规律,根据卸压瓦斯赋存特点,设计了保护层卸压瓦斯综合抽采技术:通过保护层本煤层钻孔抽采本煤层卸压瓦斯;通过顶板高位钻场钻孔抽采顶板裂隙富集瓦斯;通过沿空留巷墙体埋管抽采下煤层群卸压瓦斯.监测结果表明:被保护层煤层经卸压开采后,瓦斯抽采效果明显改善;保护层回风巷瓦斯浓度由0.58%降低至0.40%;经有效管理,沿空留巷埋管瓦斯抽采效果得到好转;保护层工作面瓦斯抽采纯量稳步提高,平均瓦斯抽采量为19.44 m^3/min,瓦斯抽采效果良好.

In order to prevent and control gas in close coal seams,the transport rule of pressure relief gas in protective seam in coal seam group was studied.According to the characteristics of pressure relief gas,extraction technology of pressure relief gas in the protective seam was designed.The gas in protective seam was extracted by the seam boreholes.The gas in roof cranny was extracted by high level borehole in roof.The gas from adjacent coal seams was extracted with pipes buried in gob-side entry retaining wall.Monitoring results showed that gas extraction effect was significantly improved after the protected seam was relieved.Gas concentration was decreased from 0.58%to 0.40%in the return airway of the protective seam.Gas extracting with pipes buried in gob-side entry retaining wall worked better through effective management.Gas extraction amount of protective seam increased steadily,and average gas extraction amount was 19.44 m^3/min,which means the effect of gas extraction was good.