Glasses and Ceramics for High-Level Waste Immobilization: An Overview – S. Miteva

According to their activity level, the radioactive wastes are categorized as high-, intermediate- and low-level waste. This report is mostly concentrated on high-level waste, which includes liquid waste from the first cycle of spent fuel reprocessing and solids into which such liquid waste has been converted. The disposal of the high-level radioactive waste consists of placing radioactive waste in a storage facility or repository, so that it is safe from unintentional disturbance in a manner which also prevents escape of any of the waste material for extremely long time periods. However it has shown to be the weakest point of the nuclear power. In this report, an overview is given of the most used materials for nuclear waste immobilization: glasses and ceramics, their properties, different types and a comparison between them. The radioactive waste is immobilized when it has reduced its potential for dispersion of contaminants in the environment and conversion of a waste into a wasteform by solidification (vitrification, cementation, bituminization) and embedding. Different types of glasses and ceramics are under development and further research.

Keywords: disposal, radioactive waste, vitrification, cementation.