Yorkshire advance in nuclear disposal

Research from Sheffield University’s faculty of engineering shows mixing plutonium-contaminated waste with blast furnace slag and turning it into glass reduces its volume by up to 95 per cent.

It also locks in the radioactive plutonium, creating a stable product.

Sheffield University says the approach could also be used to treat large volume wastes during the eventual clean-up of the damaged Fukushima plant in Japan.

Lead researcher, prof Neil Hyatt said: “The overall volume of plutonium contaminated wastes from operations and decommissioning in the UK is enough to fill the clock tower of Big Ben seven times over.

“Our process would reduce this waste volume to fit neatly within the confines of just one Big Ben tower.”

The current treatment of plutonium contaminated waste involves encapsulating it in cement – which increases its overall volume.

Prof Hyatt said: “If we can reduce the volume of waste that eventually needs to be stored and buried underground, we can reduce the costs considerably.

“At the same time, our process can stabilise the plutonium in a more corrosion-resistant material, so this should improve the safety case and public acceptability of geological disposal.”

The research was funded by Sellafield Ltd and the Engineering and Physical Sciences Research Council. Scientists carried out safe tests using the chemical cerium.

“Cerium is known to behave in similar ways to plutonium so provides a good, but safe, way to develop techniques like this,” said Prof Hyatt.

He said the end product was robust and stable because the thermal treatment destroys all plastics and organic material which would otherwise affect the movement of plutonium underground as it degrades.