多煤层穿层钻孔瓦斯抽采有效抽采半径测定

Measurement on effective gas drainage radius of boreholes passed through multi seams

为了解决煤矿瓦斯抽采过程中,测定多煤层穿层钻孔瓦斯抽采在考察区域及整个煤层的有效抽采半径时遇到的问题,分别提出了相应的解决方法:确定多煤层穿层钻孔瓦斯抽采各煤层瓦斯比例时,提出将煤层厚度、原始瓦斯含量、透气性系数的乘积作为抽采相关量,将抽采相关量归一化处理来计算,考虑了影响穿层钻孔瓦斯抽采量的主要因素;由考察区域推算整个煤层的有效抽采半径时,煤层瓦斯参数发生变化,钻孔在各煤层的瓦斯抽采量也发生变化,依据钻孔瓦斯抽采量与对应的抽采相关量成正比,推算不同煤层瓦斯参数的钻孔瓦斯抽采量。结果表明:针对青龙煤矿的实际条件,得到了16号煤层穿层钻孔在考察区域及整个煤层的有效抽采半径,为合理布孔提供了依据。

In order to solve the problems occurred in the measurement on the effective drainage radius of gas drainage with the boreholes passed through multi seams in the study area and the completed seam during the mine gas drainage process,related solutions were individually provided. When each seam gas drainage ratio was determined with the boreholes passed through multi seams for the gas drainage,the product of the seam thickness,in-situ gas content and permeability coefficient was proved as the correlated value of gas drainage and then the correlated value of the gas drainage was calculated with a normalization processing. The main factors affected to the gas drainage value of the boreholes passed through seams were considered. When the effective gas drainage radius of the whole seam was predicted with the study area,a variation of the seam gas coefficient would be occurred and the gas drainage value of the borehole in each seam would be varied. According to the borehole gas drainage value was propertional to the related drainage correlated value,the borehole gas drainage value of different seam gas parameters was predicted. The results showed that according to the actual conditions of Qinglong Mine,the effective drainage radius of boreholes passed through seams in the study area and whole seam in No. 16 coal seam was obtained and could provide the basis to the rational layout of the borehole distance.