基于CO2致裂影响的钻孔有效抽采半径研究

Study on Effective Extraction Radius Based on Influence of CO2 Fracturing

为了提高钻孔有效抽采半径,利用CO2爆破所产生的高能气体对煤体进行冲击破坏,使煤体产生裂隙网络,从而有效地增加煤层透气性,阐述了CO2爆破技术的工作原理和工艺流程,采用SF6气体示踪法对爆破钻孔进行抽采半径测试,现场试验表明:CO2爆破煤体致裂效果明显,大幅提高了羊东矿2#煤层的抽采钻孔有效抽采半径,Ф94 mm顺层钻孔抽采时间为19、35、53 d时,有效抽采半径分别达到8.0、10.0、12.0 m。

In order to improve the effective extraction radius of boreholes, the high-energy gas produced by CO2 blasting was used to impact and destroy the coal body, so that the coal body produced fracture network, which effectively increasing the permeability of the coal seam. Its working principle and technological process of CO2 blasting technology were expounded, SF6 gas tracer method was used to measure the extraction radius of blasting borehole. The results showed that the effect of CO2 blasting on coal cracking was obvious, raising the effective extraction radius of drilling hole in No.2 coal seam of Yangdong coal mine by a large margin, when Ф94 mm the hole drilled along seam extraction time was 19 days, 35 days, 53 days, the effective extraction radius was 8.0 m, 10.0 m, 12.0 m respectively.