新材料保压式封孔在瓦斯抽采钻孔中的应用

Application of borehole new material and pressure retaining sealing of gas extraction

为有效预防煤与瓦斯灾害等重大事故的发生,进一步提高钻孔效率、减少钻孔数量、煤层消突速率,煤矿现场通过采用PD材料、水泥砂浆、聚氨酯材料作为钻孔封孔材料进行试验,将三种材料封孔后测得钻孔瓦斯抽采体积分数及各种流量变化的数据进行分析。十三矿的实践表明,采用PD新型密封材料保压式封孔工艺,既有水泥砂浆的可渗透性、致密性,又有聚氨酯材料的膨胀性等优点。同时还能进一步促进材料向钻孔周围裂隙渗透,提高其封堵效果,具有较好的抗衰减性,该工艺取得了较好的抽采效果,瓦斯体积分数提高近70%,因此,具有较好的实践应用价值。

In order to prevent gas disasters and accidents,to improve the drilling efficiency,and to reduce the number of drilling and coal seam outburst elimination rate,PD material,cement mortar,and polyurethane material were used as the drilling hole sealing material for test at the scene of a coal mine. The gas extraction concentration and change of all kinds of traffic data of boreholes were analyzed after the hole sealing with three kinds of materials. Practice showed that the PD new sealing material has the advantages of both the permeability and compactness of cement mortar,as well as the swelling of polyurethane materials,etc. And also it can promote the material around the borehole fissure permeability,improve the sealing effect,and has good resistance to decay. The technology has obtained a good extraction effect,and make the gas volume fraction increased nearly 70%,therefore,it has good practical application value.