Volume of nuclear waste could be reduced by 90 percent, says new research

November 06, 2013

The researchers, from the University of Sheffield's Faculty of Engineering, have shown that mixing plutonium-contaminated waste with blast furnace slag and turning it into glass reduces its volume by 85-95 per cent. It also effectively locks in the radioactive plutonium, creating a stable end product.

The approach could also be applicable to treating large volume mixed wastes generated during the eventual clean-up of the damaged Fukushima plant.

"The overall volume of plutonium contaminated wastes from operations and decommissioning in the UK could be upwards of 31,000 m3, enough to fill the clock tower of Big Ben seven times over," says lead researcher, Professor Neil Hyatt. "Our process would reduce this waste volume to fit neatly within the confines of just one Big Ben tower."

The current treatment method for non-compactable plutonium contaminated wastes involves cement encapsulation, a process which typically increases the overall volume. Hyatt says, "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."

Although the ultimate aim for higher activity wastes is geological disposal, no disposal sites have yet been agreed in the UK.

Plutonium contaminated waste is a special type of higher activity waste, associated with plutonium production, and includes filters, used personal protective equipment (PPE) and decommissioning waste such as metals and masonry.

Using cerium as a substitute for plutonium, the Sheffield team mixed representative plutonium contaminated wastes with blast furnace slag, a commonly available by-product from steel production, and heated them to turn the material into glass, a process known as vitrification.

A key element of the research, funded by Sellafield Ltd and the Engineering and Physical Sciences Research Council (EPSRC), was to show that a single process and additive could be used to treat the expected variation of wastes produced, to ensure the technique would be cost effective.

"Cerium is known to behave in similar ways to plutonium so provides a good, but safe, way to develop techniques like this," explains Professor Hyatt. "Our method produces a robust and stable final product, because the thermal treatment destroys all plastics and organic material. This is an advantage because it is difficult to predict with certainty how the degradation of plastic and organic materials affects the movement of plutonium underground."

Professor Hyatt is now working on optimising the vitrification process to support full scale demonstration and plans future investigation of small scale plutonium experiments.
-end-


University of Sheffield

Related Engineering Articles from Brightsurf:

Re-engineering antibodies for COVID-19
Catholic University of America researcher uses 'in silico' analysis to fast-track passive immunity

Next frontier in bacterial engineering
A new technique overcomes a serious hurdle in the field of bacterial design and engineering.

COVID-19 and the role of tissue engineering
Tissue engineering has a unique set of tools and technologies for developing preventive strategies, diagnostics, and treatments that can play an important role during the ongoing COVID-19 pandemic.

Engineering the meniscus
Damage to the meniscus is common, but there remains an unmet need for improved restorative therapies that can overcome poor healing in the avascular regions.

Artificially engineering the intestine
Short bowel syndrome is a debilitating condition with few treatment options, and these treatments have limited efficacy.

Reverse engineering the fireworks of life
An interdisciplinary team of Princeton researchers has successfully reverse engineered the components and sequence of events that lead to microtubule branching.

New method for engineering metabolic pathways
Two approaches provide a faster way to create enzymes and analyze their reactions, leading to the design of more complex molecules.

Engineering for high-speed devices
A research team from the University of Delaware has developed cutting-edge technology for photonics devices that could enable faster communications between phones and computers.

Breakthrough in blood vessel engineering
Growing functional blood vessel networks is no easy task. Previously, other groups have made networks that span millimeters in size.

Next-gen batteries possible with new engineering approach
Dramatically longer-lasting, faster-charging and safer lithium metal batteries may be possible, according to Penn State research, recently published in Nature Energy.

Read More: Engineering News and Engineering Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.