Modelling of sorption-induced deformations of coal and other porous materials

Reliable models describing the sorption-induced deformations are of great importance in various industries (CO2 storage, coalbed methane production, concrete shrinkage, etc.). It is now well known that various physics are at stake, depending on the pore size. However, for materials with a very wide pore size distribution like coal or cement, no theory can predict sorption-induced deformations taking into account the full pore size distribution.
This study, based on previous works by the Navier team, aims to establish a theoretical model based on the theory of thermodynamics to describe the sorption-induced strain in porous materials with full pore size distribution, especially in coals. By applying the current model into various adsorbates and adsorbents, we show that it can predict well the shape of a strain isotherm without any fitting parameters from a desorption isotherm when limited micropores are included. Now we are trying to extend it to micropores and deal with some tricky phenomena such as cavitation.