In-situ numerical testing of CO2 sequestration in coal: effects of confining stress and injection pressure
When COz is injected, complex interactions of stress and chemistry have a strong influence on the properties of the coal. This influence is regulated by the applied confining pressure and the injection pressure. In this study, we developed a new porosity model under conditions of variable stress. A cubic relation between porosity and permeability is then introduced to relate coal storage capability (changing porosity) to coal transport characteristics (changing permeability) also under variable stress conditions. We implement these two relations into a porelastic model to represent the coupled multiphysics of coal-gas interactions. This relaxes the prior assumption that total stresses remain constant and allows exploration of in-situ stresses and variable injection pressures. Results of numerical tests under variable confining stresses and injection pressures demonstrate the controlling effects of effective stress conditions on the evolution of coal porosities and permeabilities, and the competition between effective stress effect and matrix swelling effects.
gas sorption coal deformation porosity and permeability stress effects
Z.W.Chen J.S.Liu E.Derek Z.J.Pan C.Luke
School of Mechanical Engineering, The University of Western Australia, WA, 6009, Australia Department of Energy and Mineral Engineering, Penn State University, 231 Hosier Building, University CSIRO Petroleum Resources, Private Bag 10, Clayton South, Victoria, 3169, Australia
国际会议
徐州
英文
677-685
2009-09-24（万方平台首次上网日期，不代表论文的发表时间）