明矾沟煤矿煤层瓦斯赋存规律及主控因素分析

Analysis of coalbed gas occurrence law and main controlling factors in Mingfangou Coal Mine

为了实现明矾沟煤矿煤层瓦斯精准高效治理,利用实验测试、数值模拟、数理统计、现场测试、理论分析等方法研究明矾沟煤矿瓦斯赋存规律,并从瓦斯生成、储集、赋存的角度对其赋存主控因素开展研究。研究结果表明,明矾沟煤矿煤层瓦斯含量大量分布在8 m^(3)/t以上,最高可达15 m^(3)/t,且瓦斯含量与煤层标高存在负线性关系,相近标高上下煤层之间瓦斯含量存在明显差异。矿井高瓦斯含量主要受控于高煤化阶段导致的良好瓦斯生成条件,高煤化阶段及强煤体形变破坏所导致的煤层强吸附储存能力,低透气性所导致的煤层良好保存条件;其上下煤层之间瓦斯含量主要受控于差异性煤岩组分及构造挤压效应所引起的差异性透气性及吸附能力;煤层瓦斯含量随标高降低而增加,主要受控于煤层埋深及厚度。针对瓦斯治理,矿井应采取水力压裂等技术措施,重点解决煤层低透气性问题。

In order to achieve accurate and efficient control of coal seam gas in Mingfangou Coal Mine,using experimental testing,numerical simulation,mathematical statistics,field testing,theoretical analysis and other methods to study the law of gas occurrence in Mingfangou Coal Mine,the main controlling factors of gas occurrence from the perspective of gas generation,storage and preservation were studied.The research results show that the gas content of the coal seam in Mingfangou Coal Mine is mostly distributed above 8 m^(3)/t,up to 15 m^(3)/t,and there is a negative linear relationship between the gas content and the elevation of the coal seam,and there is an obvious difference between the upper and lower coal seams with similar elevation.High gas content in mine is mainly controlled by good gas generation conditions caused by high coalification stage,strong adsorption and storage capacity of coal seam caused by high coalification stage and strong coal deformation failure,and good storage condition of coal seam caused by low permeability.Gas content between upper and lower coal seams is mainly controlled by different gas permeability and adsorption capacity caused by different coal rock components and structural extrusion effect.The increase of coal seam gas content with the decrease of elevation is mainly controlled by the depth and thickness of coal seam.In view of gas control,technical measures such as hydraulic fracturing should be adopted to solve the problem of low permeability of coal seams.