Argonne, Fermilab awarded $10M for spent fuel transmutation research

The funding is part of $40 million in funding ARPA-E made available in July 2024 through its Nuclear Energy Waste Transmutation Optimized Now (NEWTON) program, which aims to enable the economic viability of transmutation at a scale that will significantly reduce the mass, volume, activity, and effective half-life of the existing stockpile of commercial spent fuel.

Project #1: The first Argonne project was awarded $7 million and is being led by Taek K. Kim, a senior nuclear engineer and manager of Nuclear Systems Analysis. The project, titled “Liquid Lead Suspended Fuel Subcritical Fission Blanket for Nuclear Waste Transmutation,” focuses on a novel type of transmutation process based on the recoil distance and centrifugal separation of fission products from the fission of minor actinide nanoparticles from a liquid lead blanket.

The transmutation system consists of a proton accelerator, a subcritical fission blanket containing liquid lead, fission product targets, nanometer-size suspended minor actinides transmutation targets, and a separation system based on centrifugal force.

According to Argonne, the project aims to transmute the entire U.S. stockpile of minor actinides within 30 years, reducing the nuclear fuel mass by 28 times. It would also decrease radiotoxicity management time 333-fold.

“I am very excited to receive funding from the NEWTON program to advance this brand-new technology,” said Kim. “This method uses physics-based separation instead of conventional chemical separations such as PUREX, making it a separation technology that is more secure and more difficult to use for nefarious purposes.”

Project #2: Argonne’s second NEWTON project is in partnership with the DOE’s Fermilab National Accelerator Laboratory. Michael Kelly, an accelerator physicist in Argonne’s Physical Science and Engineering directorate, leads the project, “Nb3Sn Proton Driver Linac for Accelerator Driven Systems,” which is focused on developing advanced superconducting cavities used in particle accelerators.

Of the $3.2 million allocated for this project, Argonne and Fermilab are receiving about $2.2 million to develop a practical approach to reduce the size and cost of superconducting linear accelerators while simultaneously improving their reliability.

According to Argonne, Kelly and his team will leverage smaller, better-performing superconducting cavities based on an emerging technology known as thin-film niobium-tin (Nb3Sn) that is produced in a process called vapor diffusion. The new niobium-three-tin cavities would require less helium for cooling and replace today’s large, water heater–sized cavities with much smaller cavities, perhaps the size of a coffee can.

“We think it’s a big deal,” said Kelly. “We won’t know precisely what the size and cost reduction is until we do a lot more research and development. That’s a major part of what this R&D intends to address.”

Sam Posen is a senior scientist at Fermilab who is co-leading his lab's efforts in the project. “As a particle accelerator laboratory, it's thrilling for Fermilab to provide superconducting accelerator cavities and cryogenic systems, including the development of advanced niobium-three-tin coatings," Posen said. "It is a huge win when we can apply the accelerator technology we've developed to a new application with a high-impact benefit like processing nuclear waste."

Niobium-tin technology also enables the elimination of the single point of failure associated with the cryogenic plant by replacing it with a distributed set of fault-tolerant 10-watt cryocoolers. To avoid interruptions in the transmutation process, an accelerator must have an uptime of 95 percent or higher, according to Brahim Mustapha, another Argonne physicist working on the project.