| This paper represent the study of migration of 90Sr, :37Cs in a kind of aerated zone soil. The effect of some factors to the sorption of 90Sr, 137Cs in this soil was studied by static test. The chemical form distribution of 90Sr, 137Cs in this soil was determined through sequential extraction. The water dynamics nature of this soil was studied by tritium water experiment. At last, the migration of 90Sr, 137Cs in this aerated zone soil was studied through 290 days column dynamic adsorption - desorption experiment, and numerical simulation of the column experiment was studied.The distribution coefficient of sorption and equilibrium tune for Sr, Cs in this soil were measured with the static test, and the effect of soil size, material property and water phase pH value on the distribution coefficient for Sr, Cs sorption in this soil was studied. The sorption isothermal line was found to obey the Fruendlich isothermal equation. Desorption isothermal line is similar to the sorption isothermal line. The result shows that this aerated zone soil has good sorption property to 90Sr and 137Cs.Through sequential extraction, exchangeable 90Sr - which is apt to migrate-was found to be dominant state of 90Sr in the soil. 137Cs is dominantly exist as residue state in the soil, so it is not easy to migrate.Water dynamic dispersity and efficient porosity of this soil were measured by tritium water wash experiment. Value of water dynamic dispersity is 0.32cm , value of efficient porosity is 0.35.Through 290 days soil column dynamic adsorption-desorption experiment, retardation factor of 90Sr was found to be 220.4. Under this simulated rainfall condition, migration velocity of 90Sr is 0.63cm/y, on the contrary, there were almost no migration of 137Cs was found.Under the same condition as the 290 days soil column experiment, the position of concentration peak of 90Sr and 137Cs get by numerical simulation was similar to the column experiment. |
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