Journal of Nuclear Fuel Cycle and Waste Technology

Concrete materials in nuclear facilities may become contaminated or activated by various radionuclides through different mechanism. Decommissioning and dismantling of these facilities produce considerable quantities such as concrete structure, rubble. In this paper, the characteristics distribution of the radionuclide have been investigated for the effects of the heating and grinding test for aggregate size such as gravel, sand and paste from decommissioning of the TRIGA MARK II research reactor and uranium conversion plant. The experimental results showed that most of the 60Co nuclide could be removed from the gravel, sand aggregate and concentrated into a paste. Especially, we found that the heating temperature played an important role in separating the 60Co nuclide from the concrete waste. Contamination of concrete is mainly concentrated in the porous paste and not in the dense aggregate such as the gravel and sand. In test of activated concrete waste test, the clean aggregate can be recovery by up to 80%. Also, based on the results of contaminated uranium concrete, contaminated concrete volume reduced by up to 75%.

Keywords

Radioactive concrete. Contamination,Heating,Paste