Effects of salt content on leaching properties of synthetic bituminized wastes

Irisawa, Keita  ; Osone, Osamu; Meguro, Yoshihiro  

We determined the leaching ratios and effective diffusion coefficients of water-soluble components (Na, NO, NO, SO) in synthesized bituminized wastes by means of water leaching tests. Both leaching ratio and effective diffusion coefficient of the soluble component were consistent among all ionic species. This indicated that the effective diffusion coefficient for the synthesized bituminized wastes including 45wt% of the salt concentration did not depend on whether the ionic components were cations or anions or on the valence of the ion. This suggests that the interaction between the soluble components and the wall surface of the pores in the synthesized bituminized wastes was negligibly small. Moreover, the effective diffusion coefficient increased with increasing salt/bitumen ratio. We found that the effective diffusion coefficient of the soluble component was determined mainly by the salt/bitumen ratio.