Overview of recycling technologies for decommissioned materials: Lessons learned during the dismantling of a small PWR reactor

The dismantling of the BR3 research reactor produces quite large masses of contaminated materials, mainly metals or concrete. The main management routes are: conditioning of the radioactive wastes and disposal, recycling of radioactive materials in the nuclear sector and the recycling of cleared materials in the industrial sector or their disposal as industrial waste. The paper gives an overview of the main management routes followed with their associated decontamination techniques. During the dismantling of a complex system, the sorting of the materials according to the selected evacuation route is the critical point. The sorted materials are classified as homogeneous 'batches' and their follow up is guaranteed up to the final evacuation. The main processes beside the removal as radioactive waste is: Melting in a nuclear foundry either for clearance or for reuse. As Belgium does not have any 'nuclear' melting facility, contracts were signed with companies abroad; The study of recycling slightly radioactive concrete for the preparation of a 'radioactive mortar' for the conditioning of metallic radioactive waste. The R and D work is presented in this paper; Several decontamination processes are used for metals and for concrete with the objective of unconditional clearance of the materials; Abrasive processes and aggressive chemical processes are mainly used for the treatment of metallic pieces; Scabbling or shaving is mainly used for the treatment of concrete. For unconditional clearance, the issues related to the guiding values, the measurement procedures and the measurement techniques are dealt with and the experience obtained during the dismantling of our facility is presented. (author)