Experimental study on evolution of permeability of coal containing methane under confining pressure unloading condition

doi:10.16265/j.cnki.issn1003-3033.2017.08.020

Abstract

Abstract: Seepage tests were done for containing gas coal samples from Rundong no.3 coal seam to explore the extraction degree of coal seam gas in theshort-time creep process. A theoretical analysis was made for the permeability after building a permeability model. The test data and the model calculation data were analyzed. The results show that the axial pressure drop is after unloading confining pressure and is followed by permeability change, that in the early stages of unloading, permeability changes slightly and reduces slowly with the increase of the strain, then increases suddenly, that there is good consistency between the axial strain and the permeability after unloading, and that both the permeability and the strain are a exponential function of time.

Key words: permeability, creep, unloading confining pressure, dynamic models of permeability, coal containing gas

CLC Number:

X936

LI Xiaoyan, SUN Guangzhong, FU Jiangwei. Experimental study on evolution of permeability of coal containing methane under confining pressure unloading condition[J]. China Safety Science Journal, 2017, 27(8): 114-119.

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