采动影响区抽采钻井井身固化及抽采效果考察

为提高地面瓦斯抽采效果,对抽采期间钻井进行了窥视,发现当回采工作面推过地面钻井位置后,钻井井壁迅速破坏,无法充分发挥其应有的瓦斯抽采效应。通过对煤层顶板岩层受采动影响顶板活动过程的分析,优化地面抽采钻井井身结构,在原有的施工工艺上增加三开下筛管,增强钻孔的防护强度,抽采浓度提高了1.54.5倍,抽采纯量提高了1.55倍,工作面回风流和回风隅角瓦斯浓度显著下降,抽采效果明显提高。

Survey on Wellbore Cementing and Gas Drainage Effect in Drainage Borehole in Mining Influence Area

To improve the surface gas drainage effect,the author proposes optimizing the wellbore structure of surface drainage borehole by analyzing the roof movement influenced by mining and reinforcing the protection strength by adding three-phase screen pipe to the original construction technique,which can increase the drainage concentration by 1.5 to 4.5 times and the purification by 1.5 to 5 times and reduce the gas concentration of return air flow and in return airway comer with high drainage effect.