Chemical durability and characterization of low-intermediate level simulated nuclear waste glasses: Evaluation of the results obtained using multiple test methods

The thermal treatment of low and intermediate level nuclear waste allows the destruction of organic compounds by pyrolisis and the immobilization of the inorganic material in a glassy matrix. As a result, the vitrification processes are an alternative to reduce the volume of waste to be disposed, improving the quality of the final waste. Several simulated glasses were synthesized using borosilicate and alumino-silicate matrix and increasing amounts of different elements (Cs, Co...),. The glasses were characterized for: Structural configuration SEM/TEM, X-ray Diffraction, IR Spectroscopy, density, viscosity... Mechanical properties: elastic modulus (Young's M.), tensile and compression tests. Glass durability using different procedures: ASTM C-1285-97 (crushed glass), ASTM C-1220-98 (monolithic glass) and ISO 6961-1982. The results confirm that mechanical and durability-leaching properties are significantly better in vitrified waste than in cemented samples, and that the addition of oxides to the glass matrix does not affect negatively in the range 0-35 %. Best adapted tests to characterized the glass samples were also identified.