Robots to begin dismantling Dounreay’s ‘nuclear dustbin’

Friday, October 3, 2008

Robots will soon begin dismantling the plant which gave Dounreay the title of being the world's nuclear dustbin.

Workers are currently drilling through the concrete that surrounds the uranium fuel reprocessing plant which was to receive spent nuclear fuel from reactors around the world, with the waste being stored at the Caithness facility for up to 25 years; a facility that outraged environmentalists.

Now those directing Dounreay's £2.9m decommissioning have turned to specialist demolition firm Brokk to supply the remotely operated equipment that can work inside areas where radiation levels are still too high for human access.

The robots are mounted on tracks like a construction excavator and are powered by electricity.

They will go inside to cut up and package the vessels and pipes where more than 10,000 spent fuel elements were dissolved and reprocessed before the plant shut down in 1996.

After almost 40 years of operation, some of the cells are still too radioactive for people to work in. The walls and ceilings are made from reinforced concrete several feet thick, providing environmental containment and protection from the internal radiation. Stainless steel and glass-reinforced plastic has been erected outside to provide extra protection for a team wearing protective suits and respirators.

Using diamond-tipped core drills to penetrate the walls, they are drilling in a carefully designed pattern to weaken the wall sufficiently to let the first of the robots punch into the cells by the end of the year.

Once inside, the three-tonne robots will use their specially developed shears, grapples and crushers to strip out the chemical plant. Each part of the dismantled chemical works will be cut up and segregated in a dedicated waste processing structure where a platform-mounted robot will consign each item as low or intermediate-level waste after radiation checks.

Posted in |