带压注浆封孔技术在松软、高地应力煤层中的应用

Application of sealing technology with pressure in weak and high geo-stress coal seam

针对松软低透煤层瓦斯抽采钻孔普遍存在封孔质量差、漏气严重等问题,结合封孔剂及配套注浆设备提出采用"两头堵,中间注"——带压注浆封孔技术进行治理。该工艺采用矿用手动注浆泵进行注浆封孔,封孔材料选用封孔剂。此法可以增加封孔深度,加大封孔长度,有效避开巷道松动圈,并改进封孔材料与孔壁内聚力,保证封孔的密封性,进而提高抽采浓度。该技术在贵州雍和煤业有限公司四通煤矿进行了对比试验,结果表明,带压注浆封孔技术比原封孔技术瓦斯抽采浓度提高近40%,效果显著。

According to the poor borehole sealing quality, serious air leakage and other problems of the gas drainage borehole in the soft and low permeability coal seam, and with the sealing agent and grouting equipment, the paper proposed the grouting sealing under pres-sure technology which would be a two sealing and one grouting sealing technique formed. This technique used manual mine-used grou-ting pump to grouting sealing and the sealing material used the sealing agent. The method can increase the sealing depth and the sealing length, and it can effectively avoid the loose circle of the roadway. It ensured the quality of the sealing borehole by improving the bond-ing force between the sealing material and the hole wall, thereby it increased the gas concentration. A comparison experiments on the technology was conducted in Sitong Coal Mining of Guizhou Yonghe Coal Mining Group Corporation Ltd. The results show that the pres-surized borehole sealing technology could improve the gas concentration by 40% higher than the previous borehole sealing technology with obvious effects.