Thermal Treatment of Irradiated Graphite

A key challenge in the decommissioning of UK and international nuclear facilities is the management of irradiated graphite. Graphite is used as a neutron moderator, reflector, etc in most of the UK’s reactors , and is a very bulky material which is difficult to remove intact from the reactor core at the end of life. If it is removed from the core it represents a large , and hence expensive, waste stream for storage and subsequent disposal. This has led to the current strategy of leaving graphite "in-situ" in shut down reactors until waste facilities become available. This proposal relates to a new and innovative method for accelerated graphite management which would convert the graphite to carbon dioxide which could then be incorporated in a carbon capture and storage scheme: such storage schemes are now under development in the UK at commercial scale. The small residue (5-10% of the original waste volume) containing the majority of the non-volatile radioactive material would be treated conventionally. The proposed project is an essential step in securing this new method of graphite management.