Experimental study on effect of pore pressure on permeability of coal

doi:10.16265/j.cnki.issn1003-3033.2017.03.014

Abstract

Abstract: In order to study influence of pore pressure on permeability of coal and gas migration law, pore characteristics of samples of two kinds of coal taken from Liupanshui mining area were studied by using a scanning electron microscope (SEM) with energy dispersive X-ray (EDX) and a specific surface area and micropore analyzer,and seepage experiments were carried out on the samples by using an independently developed traixial seepage device. The results show that the pore characteristics of coal and the amount of nitrogen adsorption are positively correlated with the pore fissure development degree, and also related to the pore connectivity,that when the pressure difference is constant, the permeability of coal decreases exponentially with the pore pressure, and when the pressure difference is small, the decrease rate of permeability decreases with the increase of pore pressure,and that the permeability of coal decreases exponentially with the increase of pressure difference between the two ends of the specimen.

Key words: coal, pore pressure, effective stress, permeability, pressure difference

CLC Number:

X936

LI Bobo, YANG Kang , YUAN Mei, XU Jiang. Experimental study on effect of pore pressure on permeability of coal[J]. China Safety Science Journal, 2017, 27(3): 77-82.

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