NDA's Radioactive Waste Management Directorate (RWMD) has published independent research by Quintessa commissioned to review the performance of five potential metals that could be used in the manufacture of canisters for the disposal of High Level Waste (HLW) and Spent Fuel (SF) in a geological disposal facility.
At this stage no site for a facility has been selected and Government is leading the search for a site based on voluntarism and partnership with potential host communities. The research therefore considers the use of the metals in a variety of geological environments and focuses particularly on the period following the eventual closure of a facility. The potential canister materials are:
- copper
- carbon steel
- titanium alloys
- nickel alloys and
- stainless steels.
Lead has also been considered as a material to be used inside the canister. Cristiano Padovani, RWMD's Corrosion Specialist said:
"The researchers found the five candidate canister materials considered offered different advantages and disadvantages."This research provides us with information that will be of use to us for the option studies we will carry out in the future when selecting an engineered barrier system (EBS) design to be used once a site has been selected."
The review is limited to the corrosion behaviour of these metals and no consideration is given to either the canister design or the mechanical performance. Further studies will be required to discuss these aspects in greater detail. The report 'Review of the corrosion performance of selected metals as canister materials for UK spent fuel and/or HLW' can be downloaded from the NDA bibliography.
The report concluded that based on the corrosion performance, canister materials have been identified for a range of disposal conditions. Cristiano said:
"This work will help us to make informed decisions when we reach the time that a site for geological disposal becomes available."
Image courtesy of SKB