The aim of this project is to develop and test a process which will allow long term storage of Magnox Fuel in dry conditions, prior to disposal.
It is possible that a small quantity of Magnox fuel may not be reprocessed. Experience from the First Generation Fuel Storage ponds at Sellafield site shows us that wet storage of Magnox fuels is not possible for long periods. Therefore, an alternative solution is required for storage of Magnox fuel between reactor discharge and final disposal.
Wylfa has experience of storing fuel, freshly discharged from the reactor, in a purpose built dry store. Therefore technical feasibility for uncorroded fuel, with self heating, is proven; as long as the fuel remains dry. There are reports that if the fuel is accidentally wetted, then the cladding corrodes leading to the risk of activity release. If this is the case, then the sensitivity to even a short term exposure to water will greatly affect the possibility of long term storage.
The main question that this project will address is whether fuel that has already been stored and cooled in wet conditions can be dried and passivated sufficiently to allow long term storage without (further) degradation.
The project will consist of the following tasks:
1) Identify the likely cladding chemistry of wet stored Magnox fuel.
2) Recreate this cladding to establish surrogate materials for testing.
3) Determine the optimum physical conditions (pressure, temperature and time) for drying.
4) Determine the effect of gas composition on cladding chemistry.
5) Determine the effect of irradiation.
6) Investigate cladding stability during long term storage.
Output from the project will be fed into the NDA’s spent fuel forum
Contact: Prof Bruce Hanson