This study explores the corrosion interactions between a metallic canister material, stainless steel (SS) 316, and an I-bearing ceramic waste form, lead vanado-iodoapatite (I-APT, Pb9.85(VO4)6I1.7), in a chloride solution. Crevice corrosion of the SS in close proximity to the I-APT resulted in the development of an aggressive environment at the interface of the two materials, which was acidic and enriched in Cl− anions. I-APT also corroded in the crevice region, primarily through ion-exchange between the I− ions from the I-APT matrix and anions from the environment. The enrichment of Cl− anions within the occluded crevice space as the result of SS crevice corrosion enhanced the corrosion of I-APT. The release of iodine from this apatite waste form could be accelerated owing to this mechanism. This is evidenced by a depletion of iodine from the I-APT matrix and a large amount of Cl-bearing precipitates on the surfaces of both SS and I-APT. On the other hand, the corrosion of I-APT leads to the precipitation of a V- and Pb-rich layer, which inhibits the localized corrosion of SS to an extent. This study advances the understanding of the near-field corrosion interactions between metallic canisters and ceramic waste forms.
Nature 12th May 2020 read more »
Radiation shielding materials such as lead could be replaced with a material consisting of a polymer compound embedded with bismuth trioxide particles, claim researchers at North Carolina State University.
The Engineer 12th May 2020 read more »
Jacobs has been selected by Radioactive Waste Management Ltd (RWM), a subsidiary of the Government’s Nuclear Decommissioning Authority, to work on a project linked to the decommissioning of UK nuclear power stations. The group, which has operations in Cheshire and Manchester, will study the release of radioactivity from irradiated graphite sampled from reactor cores at the UK’s nuclear power stations. This research will support RWM in its analysis of graphite behaviour and the options for graphite waste management in the future. Clive White, Jacobs’ critical mission solutions senior vice president, said: “We’re combining our leading graphite knowledge from our integrated waste management team at Harwell, our role as designer and architect engineer of the Advanced Gas Reactor (AGR), and Magnox reactors, and our work on operational support and life extension. The research will have a significant bearing on the safe management and disposal of graphite wastes arising from the decommissioning of 14 advanced gas-cooled reactors (AGR), which generate nearly 20% of the country’s electricity, but are due to be phased out over the next 10 years. The contract has an initial duration of two years but, subject to experimental programme results, it may be extended by an additional two years.
Business Desk 12th May 2020 read more »
Power Engineering 12th May 2020 read more »