Study on the Migration of Radionuclide Cs and Pu in Backfill Materials

Based on the analysis of radionuclide migration scene, the physical model of radionuclide migration in backfill materials is established, and the analytical solution model of the equation is given. According to reasonable settings and parameters obtained from the experimental research, the simulation study on the migration rule of radionuclide 137Cs and 239Pu in the backfill material is carried out. Through the analysis of relevant factors affecting the radionuclide migration of 137Cs and 239Pu, such as compaction density, distribution coefficient and migration time, and the evaluation of the safety performance of backfill materials, it is concluded that the backfill materials with high compaction density and large distribution coefficient can effectively block radionuclide migration to the external environment.