Leaching of the Matrix with Radioactive Waste under Disposal Conditions on the Example of Model Phosphate Glass

摘要

A new approach to the study and description of leaching processes was proposed based on the fundamental difference in water exchange regimes during technological tests of confinement matrices of radioactive wastes (RW) according to standard leaching techniques and in the interaction of conditioned solid RW with groundwater under disposal conditions. According to this approach, in the leaching of matrices in a closed system, the main parameters characterizing the result of the process are the concentrations (specific activities) of saturation of the leachate with matrix elements and radionuclides. The proposed approach is illustrated by the example of calculating the leaching parameters of a model phosphate glass with imitators of radioactive waste, carried out using an appropriate kinetic model based on the data of experiments conducted in a static mode (in the absence of water exchange). The found values of the saturation concentrations of leaching solutions with matrix elements can be used to perform experiments and calculations on the migration of radionuclides in the materials of engineering barriers and host rocks.