Research on coal permeability model considering proppant embedding

doi:10.16265/j.cnki.issn1003-3033.2019.11.003

Abstract

Abstract: In order to study permeability evolution mechanism under coupling effects of proppant and stress during coalbed methane extraction process, a coal adsorption deformation equation was established by using adsorption theory. Then, a permeability model considering proppant and stress was further constructed and verified through test data. The results show that coal adsorption and pore pressure is positively correlated and adsorption-induced deformation also has the same trend. Permeability of coal embedded in proppant is much greater than that in conventional reservoir, among which monolayer has the best anti-reflection effect. Coal permeability would decrease in form of an exponential function as effective stress increases, but will decrease first and then tend to change gently with the increase of pore pressure. Measured values are basically consistent with calculated values of an improved theoretical model as it is used to fit the curve.

Key words: proppant, pore pressure, adsorption model, coal, permeability

CLC Number:

X936

LI Bobo, LI Jianhua, YANG Kang, REN Chonghong, XU Jiang. Research on coal permeability model considering proppant embedding[J]. China Safety Science Journal, 2019, 29(11): 14-19.

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