西山矿区煤层顺层孔CO_2爆破增透试验研究

Experimental Study on CO_2 Blasting Pre-splitting of Bedding Hole in Xishan Coal Mining Area Coal Seam

为提高西山矿区煤层透气性,缩短瓦斯抽采达标时间,分析了煤层顺层孔CO_2预裂增透技术可行性,模拟了CO_2预裂增透半径。研究结果表明:CO_2爆生气体计算压力大于围岩作用下煤体强度,CO_2爆破煤层增透具备技术可行性;数值模拟显示,经过CO_2预裂爆破后,预裂效果最好的是屯兰矿2#煤,煤层裂隙半径4.20 m;其次是屯兰矿8#煤,煤层裂隙半径3.90 m;再次是马兰矿8#煤,煤层裂隙半径3.45 m;最后是东曲矿8#煤,煤层裂隙半径3.30 m.现场试验表明,东曲矿8#煤爆破孔间距按65 m布置,压裂区平均单孔抽采纯流量是未压裂区的32倍。

In order to improve the coal seam permeability of Xishan mining area,shorten the time of gas drainage standard,the feasibility of CO_2 blasting pre-splitting technology in coal seam is analyzed. The CO_2 blasting presplitting radius is simulated. The results show that CO_2 detonation pressure is greater than the strength of coal,coal seam permeability can be increased by using CO_2 blasting. Simulation shows that pre-splitting effect of No. 2 coal in Tunlan coal mine is the best,the fracture radius is 4. 20 m,the fracture radius of No. 8 coal in Tunlan coal mine is3. 90 m,the fracture radius of No. 8 coal in Malan coal mine is 3. 45 m,the fracture radius of No. 8 coal in Dongqu coal mine is 3. 30 m. The field test shows that the average flow rate of single hole drainage in fractured zone is 3. 2times of non-fractured zone when the blasting hole spacing of No. 8 coal in Dongqu coal mine is 65 m.