Nuclear scientists advance a technology for more efficient uranium and rare earth element recovery.
Nuclear energy has enormous potential to power current and future energy needs. To advance this potential, scientists at the U.S. Department of Energy's (DOE) Argonne National Laboratory are researching a technology that relies on a smaller, more local approach to efficient uranium and transuranic element recovery. The impact of the research may extend beyond nuclear fuel recycling to applications in other metal recovery processes such as rare earth recovery.
The versatility of the scalable solution suggests that the U.S. could extract more out of materials that would otherwise end up in landfills, such as mining waste, coal fly ash or discarded electronics. This could help the U.S. manufacturing industry on multiple fronts. It could improve and broaden U.S. options for increased use of safe, secure domestic sources of nuclear and other types of energy.
Anna Servis, a radiochemist at Argonne, spearheaded the research, which was funded by DOE's Advanced Research Projects Agency–Energy. She and her team focus on efficient metals production and are developing groundbreaking chemical process equipment known as rotating packed bed (RPB) contactors.
These innovative devices are designed to optimize traditional chemical processing methods. However, due to their small size and range of functions, they can be used at multiple manufacturing or nuclear energy sites. This can significantly reduce the size, safety and cost barriers traditionally associated with nuclear fuel recycling.
Currently, the U.S. faces challenges reusing or disposing of used nuclear fuel, which largely remains stored at reactor sites nationwide. By recycling used fuel at or near the site where the fuel is initially used, RPB technologies aim to minimize risks associated with its transportation and storage. For example, large containers of used nuclear fuel would not need to travel from point A to point B via U.S. roadways. The smaller-scale, more local approach to recycling materials would be attractive to the public, less expensive to achieve and include multiple other safety efficiencies.
"The stakes are high in the nuclear industry, and so is the potential for impactful innovation," said Servis. She noted that smaller-volume RPB contactors could replace larger, more cumbersome equipment. This would reduce the amount of costly safety shielding typically required to protect workers against radiation.
Servis and her team are exploring three different approaches that use RPB technology to extract uranium and transuranic elements, and rare earth elements: gas scrubbing, liquid-liquid extraction and solid phase extraction. In each approach, they capitalize on a state of matter - gas, liquid or solid - to separate wanted materials from unwanted. Once the desired materials are isolated in a new stream or solution, they can be recovered. The unwanted materials, meanwhile, can be discarded in smaller, less hazardous quantities.
Argonne collaborates on this research with Case Western Reserve University.
"Our research is not just about refining technologies, it's about redefining possibilities," Servis said.