宁东矿区瓦斯风化带内的瓦斯异常分析

Analysis of abnormal gas in gas weathered zone of Ningdong mining area

在瓦斯风化带内开采煤层,瓦斯一般不会对生产构成主要威胁,但笔者在宁东矿区某矿瓦斯风化带内施工地质检查孔时却发现了高浓度的甲烷气体。通过区域地质分析和工程探测研究,发现该区域因受地质构造影响,在顶板砂岩中有游离瓦斯聚集,经过针对性钻孔抽采,3个月抽采了近200万m3的纯瓦斯。这说明在封闭条件下的瓦斯风化带内,仍可能出现瓦斯集中赋存的区域。

During mining in gas weathered zone,the gas is not a major threat to production.But in this research,the high concentration of methane gas is found from the geological inspection drilling in the gas weathered zone for colliery construction.Through regional geological analysis and the geology exploration,it is found that in the initial district in arched structure zone,there is free gas accumulation in sandstone in roof due to the influence of geological structure.Through targeted gas drainage by boreholes,nearly 200 million m3 of pure gas were drained during 3 months.The study results indicated that there may exist an area with high gas concentration in gas weathered zone with closure conditions.