Why shale permeability changes under variable effective stresses: New insights

doi:10.1016/j.fuel.2017.10.068

CORC > 武汉岩土力学研究所 > 中科院武汉岩土力学所 > 岩土力学所知识全产出 > 期刊论文

	Why shale permeability changes under variable effective stresses: New insights
	Cui, Guanglei 2,3; Liu, Jishan 4,5; Wei, Mingyao 2; Shi, Rui 1,2; Elsworth, Derek 6
刊名	FUEL
	2018
卷号	213 页码:55-71
关键词	Shale apparent permeability Constant effective stress Deformation evolution Gas diffusion
ISSN号	0016-2361
DOI	10.1016/j.fuel.2017.10.068
英文摘要	Experimental measurements of shale permeability are normally conducted under conditions of constant effective stresses. Based on the theory of poroelasticity, shale permeability in non-sorbing media is determined by the effective stress alone and remains unchanged if the effective stress does not change. This theoretical conclusion contradicts some experimental observations in sorbing media. These enigmatic phenomena are analyzed through a model accommodating gas slippage. This approach can explain why shale permeability is significant at low gas pressure but does not explain the contradiction with poromechanics. In this work, we develop and apply an alternative approach to resolve this dilemma. The model comprises flow within a nanotube capillary embedded within the shale matrix (discrete approach) and allows the evolution of shale permeability to be followed during the processes of shale gas flow. In the formulation, we define four strains: global strain of the shale, fracture-local strain, matrix-global strain, and pore-local strain. Shale permeability is defined as a function of these strains that are, in turn, a consequence of effective stress transfer between the matrix and the fracture systems. This behavior is regulated by the differential compliance of the various components and by gas diffusion from the fracture system to the matrix. We use the strain evolution to define how shale permeability changes with time or gas pressure in the matrix system. We apply the new model to generate a series of shale permeability profiles. These profiles are consistent with experimental observations reported in the literature. Through this study, we demonstrate that the experimental observations can indeed be explained through the inclusion of explicit interactions between shale microstructures and gas transport processes.
WOS研究方向	Energy & Fuels ; Engineering
语种	英语
出版者	ELSEVIER SCI LTD
WOS记录号	WOS:000414924700006
内容类型	期刊论文
源URL	[http://119.78.100.198/handle/2S6PX9GI/4202]
专题	岩土力学所知识全产出_期刊论文国家重点实验室知识产出_期刊论文
作者单位	1.China Univ Geosci, Fac Earth Resources, Key Lab Tecton & Petr Resources ; 2.Chinese Acad Sci, Inst Rock & Soil Mech, State Key Lab Geomech & Geotech Engn ; 3.Univ Chinese Acad Sci ; 4.Northeastern Univ, Minist Educ Safe Min Deep Met Mines, Key Lab, IRC Unconvent Geomech ; 5.Univ Western Australia, Sch Mech & Chem Engn; 6.Penn State Univ, Dept Energy & Mineral Engn
推荐引用方式 GB/T 7714	Cui, Guanglei,Liu, Jishan,Wei, Mingyao,et al. Why shale permeability changes under variable effective stresses: New insights[J]. FUEL,2018,213:55-71.
APA	Cui, Guanglei,Liu, Jishan,Wei, Mingyao,Shi, Rui,&Elsworth, Derek.(2018).Why shale permeability changes under variable effective stresses: New insights.FUEL,213,55-71.
MLA	Cui, Guanglei,et al."Why shale permeability changes under variable effective stresses: New insights".FUEL 213(2018):55-71.