Nuclear Waste Glasses

In the European Union, the main sources of nuclear waste include both low-level waste (LLW) generated from the dismantling of nuclear weapons, and high-level waste (HLW) such as spent nuclear fuel from nuclear reactors as well as the liquid waste generated from the reprocessing of spent nuclear fuel. In order to retain radioactive elements in the event of water intrusion into the repository, solid waste forms such as ceramic, cement and glass have been an important area in nuclear research. Although nuclear waste is often stored in a container isolated from the environment, waste containment material still governs the retention of active species. Around the world, borosilicate glasses have been the most widely adopted material for the immobilization of both HLW and LLW. In addition to the chemical durability, mechanical integrity and thermal stability, borosilicate glasses are flexible with waste loadings and possess the capability of incorporating most of the waste elements. One of the goals of our research in nuclear waste confinement regards the investigation of the structure of borosilicate glasses, how waste elements are incorporated into them and how they affect important macroscopic properties such as durability and mechanical properties.