CONCEPTUAL DESIGN FOR REMOVAL OF THORIUM

Client:
UKAEA, Winfrith

Description:
UKAEA were to restart a project to remove, process and safe store 11 tonnes of thorium rods that are currently held in an underground vault. The thorium is radiologically hazardous and known to be pyrophoric and needs to be handled carefully to avoid initiating combustion.

The rods are stored in old ammunition boxes, some of which are in poor condition. Nuclear Technologies were asked to provide a briefing document to help define the tasks ahead. This was accomplished in the form of a series of sequential diagrams indicating a cradle to grave solution to be presented at the start up meeting.

Scope of service supplied

Diagrams were prepared to show:

• Retrieval of the ammunition boxes from the vaults within an over-pack

• Transportation of the over-pack to a treatment facility

• Transfer of ammunition box from over-pack to shielded enclosure

• Removal of thorium rods

• Inspection of rods

• Placing of rods in stillage

• Lowering stillage into 200 litre drum

• Grouting of drum/thorium rods for long-term storage.

These sketches provided an outline of the type of plant and equipment required to process the thorium and included a cost/programme estimate.