Study on the Elution of Radionuclides from Solidified Wastes

Effective Diffusion Coefficients of Ions in Some Porous Bodies

Abstract

The leak of radionuclides from a disposed container depends on some rate processes such as the dissolution of the surface of the solidified waste and the diffusion in the solidified body and the wall of the container. Concerning the diffusion processes, several methods to determine the effective diffusion coefficient were reviewed and newly developed theoretically in the former paper. Based on the one of them, effective diffusion coefficient of ³H₂O, NH₄Cl in the porous media such as cement paste, mortar, gel and the packed bed of resin-balls were measured and compared with the theory in this paper. And then the coefficients were explained in connection with the structure of these porous media with the concept of tortuosity factor.