11:30 AM - 11:45 AM
[1D05] Changes of mass transfer and porosity distribution in porous media, considering a drying process before the closure of repository
Keywords:Geological disposal, Porous media, Drying, Porosity, X-ray CT
In geological disposal, the tunnel in the repository will have been ventilated for at least 50 years before the closure, and a drying area expands around the repository. Such a drying process accumulates a solute toward the drying surface with evaporation of solvent (water) and capillary force. Applying this phenomenon to the mass transfer around the repository, silica components would be transported toward the tunnels of the repository, because a highly alkaline environment derived from concrete can solve a large amount of silicic acid. This study focused on the change in porosity during the drying process. By drying a wet porous material packed bed with given initial concentrations of some kinds of solutes, the effect of the solute concentration and the particle size on the drying rate were examined. And the porosity was evaluated using the X-ray CT values after a drying process. In the results, the behavior of mass transfer and the change in porosity during drying were quantitatively clarified.