含瓦斯煤渗透性影响分析

Analysis on Influence of Gas Coal Permeability

以屯兰矿8#煤层低渗透含瓦斯煤为研究对象,采用电液伺服渗流装置进行了轴压、围压与瓦斯压力的交叉试验,以分析含瓦斯煤渗透性影响因素及其重要程度。结果表明,在恒定的应力场中,含水率的变化对于煤体渗流特性影响很大,渗透率的变化与含水率呈现负指数函数形式,与轴压、围压也呈现负指数函数变化;通过比较拟合函数中的拟合系数a发现在含瓦斯煤渗透性影响因素中,瓦斯压力对煤体渗透性影响最大,围压对渗透性影响的重要程度次之,轴压影响程度最小。

The factors affecting the permeability of gas-bearing coal are studied and their importance is analyzed in Tunlan mine.The results show that in a constant stress field,the change of water content has a great influence on the permeability characteristics of coal.The change of permeability and water content take the form of a negative exponential function,and the axial pressure and confining pressure also show a negative exponential function change;Comparing the fitting coefficient A in the fitting function,it is found that among the influencing factors of gas coal permeability,gas pressure has the greatest impact on coal permeability,surrounding rock pressure has the second most important impact on permeability,and axial pressure has the least impact.