STUDY OF THE CONDITIONING MATRICES FOR ALUMINIUM RADIOACTIVE WASTES

Embedding of radioactive waste in Portland cement matrix is the most used method applied worldwide, but not all the radioactive waste types are compatible with the normal cement matrix because of negative effects of some chemical reactions developed during the hydrolysis and curing steps of cement paste. The radioactive aluminium, one of the as called "hazardous wastes" generated by the decommissioning of research nuclear reactor as VVR-S - IFIN-HH, or other nuclear techniques applications like irradiation/activation techniques, is a type of radioactive waste which can not be conditioned by this method, due to behaviour of the metallic aluminium in contact with normal cement products. The studies and preliminary results of the work presented in the present paper is part of a research project developed to identify a proper management of this special type of radioactive waste from the storage phase up to final disposal. To obtain a conditioning matrix for radioactive aluminium in accordance with the international disposal requirements and respecting the waste acceptance criteria of the National Radioactive Waste Repository - Baita-Bihor, is necessary to study new formulas of low basicity binding agents, in order to minimize the alkaline attack of cement hydrolysis products on metallic aluminium.