摘要
针对低透气性高瓦斯煤层,开发了液态CO2深孔预裂爆破技术及装备。阐述液态CO2预裂爆破的机理并开展现场试验。试验表明,预裂爆破后影响半径可达12m以上,抽采负压最大达到13998.8Pa;预裂钻孔及其影响范围内的抽放钻孔瓦斯浓度都有明显上升,部分钻孔抽采浓度能提高50%以上;预裂后钻孔瓦斯抽采流量显著提高,单孔最大抽采量达385.8m3/d,累计瓦斯抽采量能达到普通钻孔累计瓦斯抽采量的2~6倍;预裂后日均瓦斯抽采量长时间维持在一个较高水平,衰减系数不到普通钻孔的1/2。
The technique and equipment of deep holepresplitting blasting with liquid carbon dioxide were developed for low permeability and high gas coal seams.The mechanism of presplitting blasting with liquid carbon dioxide was proposed and field tests were carried out.The experiments show that the influence radius of the presplitting blasting can reach to 12 mabove,the negative pressure of extraction reaches a maximum of 13998.8Pa;the gas concentration of the drainage boreholes in the presplitting drilling and its influence scope has increased significantly,and the extraction concentration of gas in parts of boreholes can increase more than 50%;the gas extraction volume in the boreholes after presplitting significantly improved,the maximum extraction volume of single hole was 385.8m3/d,and the accumulative gas drainage volume was 2~6times the ordinary＇s.after presplitting,the daily gas drainage amount maintained at a high level for a long time,and attenuation coefficient was lower than 1/2of the conventional boreholes.
出处
《中国煤炭》
北大核心
2015年第8期112-115,共4页
China Coal
关键词
液态CO2
预裂爆破
影响半径
卸压增透
liquid carbon dioxide
presplitting blasting
influence radius
depressurization and enhanced permeability
