低透气性软煤层筛管护孔与CO_2相变致裂增透技术的联合应用

Joint Application Research on Screen Pipe Protection Hole and CO_2 Phase Change Fracturing Technology in Low Permeability and Soft Coal Seam

针对部分矿井煤层透气性差且煤质较软的特点,采用筛管护孔与CO_2相变致裂增透技术的联合应用进行现场试验研究,得出针对某矿当爆破深度为30 m时,采用50 m的筛管进行护孔相比未施工爆破孔且未下筛管的钻孔平均单孔瓦斯混合流量提高了4.2倍,瓦斯浓度提高了1.5倍,而相比只进行CO_2相变致裂增透而未下筛管的钻孔平均单孔瓦斯混合流量提高了2.4倍,瓦斯浓度提高了1.2倍。

Aiming at the features of low permeability and soft coal quality in coal seams of some mines,the field experiment research was carried out through the joint application of screen pipe protection hole and CO_2 phase change fracturing technology,it has been found that when the blasting depth is 30 meters to a mine,the gas extraction and concentration in single hole with 50 meters screen pipe protection hole increased an average of 4.2 times and 1.5 times compared to the drilling without blasting hole and screen pipe,and the gas extraction and concentration in single hole increased an average of 2.4 times and 1.2 times compared with the singe CO_2 phase change fracturing without screen pipe protection hole.