Four monster tanks are ready to be removed from the prototype fast reactor’s steam generation building at Dounreay.
The tanks were an important part of the reactor’s secondary sodium circuit, which transferred heat from the reactor to the steam turbine.
Three of the 9m high tanks formed part of the reactor’s protection system, where sodium from the secondary circuits could be dumped in case of emergency. Each tank was capable of holding 67.5 tonnes, and could be filled in a matter of a few minutes.
The fourth and largest tank, capable of holding 110 tonnes, was part of the system that cleaned and filtered the sodium before it was pumped back into the secondary sodium circuit.
A team of workers from Sureclean, the site’s specialist asbestos removal contractor, removed the 20cm thick lagging from around the tanks, supported by JCL’s scaffold service and JGL Engineering & Technical Services.
With the lagging removed and the pipework disconnected, the support structures around each tank will be dismantled, including the cell roofs. The tanks will then be craned out of their cells, before they are cut up and the solidified sodium dug out by the AMRR Alliance team – DSRL, JGC Engineering, BNS Nuclear Services and Jacobs Ltd.