The destruction of one of the highest hazards remaining in the Nuclear Decommissioning Authority (NDA) estate has been completed at Dounreay. Around 68 tonnes of highly radioactive liquid metal coolant was removed from the Dounreay Fast Reactor (DFR) and safely destroyed over a ten year period. The liquid metal, a blend of sodium and potassium called NaK, was used to remove heat from the reactor’s nuclear fuel. Dounreay used a specially built plant and removal system to safely convert the NaK to hydrogen gas and salt water. Handling the material is a particularly complex technical challenge as it reacts vigorously when exposed to air or water, eventually catching fire. This meant that it had to be kept under a nitrogen gas blanket to prevent reactions.
DSRL 5th Aug 2016 read more »