阜新盆地煤层气渗流规律实验

Experimental study of coalbed methane seepage in fuxin basin

以阜新盆地王营煤矿采集加工的原煤煤样为研究对象,利用3轴渗透仪,对煤样的渗透率和有效应力之间的变化关系以及煤样中甲烷渗流规律进行了实验研究。实验结果表明,煤样渗透率具有应力敏感性,渗透率随有效应力的增加呈非线性递减关系,具有负指数规律,这与前人的研究结果吻合较好;在不同围压、含水率情况下,实验得到的甲烷渗流规律曲线具有明显的非线性特征,真实地反映了实验过程中煤体变形对甲烷渗流的作用。考虑有效应力对煤体变形的影响,建立了描述煤层甲烷非线性渗流特征的运动方程,且所建立的运动方程与实验数据具有很好的吻合性,拟合相关系数高达99.6%以上,说明实验方法和建立的运动方程是合理的。

Taking raw coal samples collected from the wangying colliery in Fuxin basin as the research object,the experiment of coalbed methane seepage law is conducted by the triaxial osmoscope and the relationship between effective stress and coal permeability is presented.The experiment results indicate that the coal permeability is of stress sensitivity and tended to decline in exponent with the increment of effective stress,which is consistent with the former research results.The seepage flow curves from experiments demonstrate the nonlinear characteristics under different confining pressures and moisture contents,and it accurately reflecte the effect of coal body deformation on the coalbed methane seepage flow in the experimental process.Therefore considering the influence of effective stress on the coal body deformation,a new motion equation for the nonlinear percolation characteristic of coalbed methane is established.Moreover,the motion equation is correlated well with the experimental data,and the fitting correlation coefficients are above 99.6%.