羽状千米长钻孔抽采效果考察试验

The testing of gas drainage efficiency about feather-veined 1000 m length-drillhole

探讨了羽状千米顺层长钻孔区域性预抽煤层瓦斯的特点和优越性,结合煤层瓦斯抽放理论,分析了钻孔瓦斯流量与负压及钻孔长度的关系,指出千米钻孔工艺是针对高瓦斯矿井区域性防突措施和井下煤层气开采的一种新型抽采技术。在山西晋城无烟煤矿业集团有限责任公司寺河煤矿西轨措施巷1号和2号千米钻孔的应用研究表明:区域煤层瓦斯预抽率可达42%以上,且在煤层透气性系数和抽放负压条件相对不变的前提下,钻孔越长,百米钻孔初始瓦斯流量就越大,衰减系数随之减小,相同的时间内抽采率亦相应升高。

Studied the areal gas drainage characteristics and advantage of feather-veined 1 000 m longitudinal length- drillhole, combined with coal seam gas drainage principle, analyzed the relationship between drillhole gas flow and negative pressure,length of drillhole, pointed out that 1 000 m length-drillhole was a new technology which applied to areal prevention of gas outburst and underground coalbed methane drainage in gassy mine. As the technology applied to Nos. 1 and 2,1 000 m length-drillhole which in the west gathering main roadway of Sihe Coal Mine, Shanxi Jincheng Anthracite Coal Mining Group Co. Ltd. , the effect indicates that the areal gas drainage from virgin coal seam rate can reach more than 42%, under the relative invariant condition of gas permeability coefficient and drainage negative pressure,the longer the drillhole is,the more the drillhole gas flux per 100 meters and the smaller the attenuation coefficient, so the gas drainage efficiency will increase in identical time.