Some factors controlling diffusive transport of potassium ion through clayey soils

摘要

To investigate the potential use of two Japanese regional clayey soils, named Ariake clay and Akaboku soil, as soil barrier materials, a series of laboratory diffusion tests are presented. Using an available computer program Pollute V6.3, the effective diffusion coefficients of K~+ of the soils were back-calculated from the diffusion tests. It is found that the Ariake clay has a larger effective diffusion coefficient than the Akaboku soil, indicating that the Ariake clay may provide a better diffusion barrier. A comparison of the effective diffusion coefficients between the single-salt solution condition and the multi-salt solution condition indicates that soils have higher effective diffusion coefficients under the former condition. It is suggested to use miscible solution close to landfill leachates for determining effective diffusion coefficients of specified chemical species for a practical design.