瓦斯抽采新型封孔装置的研究与应用

Research and Application of New Sealing Device for Gas Drainage

针对瓦斯抽采钻孔因封孔失效导致抽采效果不佳的情况,通过对钻孔漏气机理分析,提出瓦斯抽采钻孔3种典型漏气形式。结合“两堵一注”封孔装置的不足,提出一种新型瓦斯抽采钻孔封孔装置,通过“一管多用,多管合一”的结构设计,消除了封孔囊袋与抽采管路间的漏浆通道,提高封孔注浆压力。现场实验表明,在抽采50 d后,新型封孔工艺较聚氨酯封孔法、“两堵一注”封孔法的瓦斯抽采体积分数分别提升了49.50%和11.85%;瓦斯抽采纯量分别提升了43.75%和9.52%。

Aimed at the situation that the gas extraction drilling is not effective due to the failure of sealing hole, through the analysis of the mechanism of gas leakage, three typical gas leakage forms of gas extraction drilling are proposed. Combined with the deficiency of "two sealing and one grouting" sealing device, a new sealing device for gas extraction drilling is proposed. Through the structural design of "one pipe is multi-purpose, multi-pipe is integrated", the leakage channel between the sealing bag and the pumping pipeline is eliminated, and the grouting pressure of sealing hole is improved. Field experiments show that compared with the polyurethane sealing method and "two sealing and one grouting" sealing method, the volume fraction of gas extraction is increased by 49.50% and11.85%, respectively, after 50 days of drainage. The pure volume of gas extraction increased by 43.75% and 9.52%, respectively.