Russian state nuclear corporation Rosatom has announced a significant breakthrough in the decommissioning of fast neutron nuclear reactors with the development of a new technology for processing liquid radioactive sodium coolant.
“The developed equipment allows liquid sodium to be converted into a solid mineral-like product suitable for final disposal,” said Rosatom.
The state nuclear corporation has highlighted several key advantages of this new technology and its “Mineral 100/150” plant. These included the complete absence of gas emissions, enhanced explosion and fire safety, and a simplified, single-stage technological process.
This development marks a crucial step forward in safely and effectively decommissioning aging nuclear facilities that utilize liquid sodium as a coolant.
Streamlining decommissioning of fast neutron reactors
The technology, created at the Leypunsky Institute of Physics and Power Engineering for Rosatom’s fuel division, TVEL, has the potential to streamline the decommissioning process for several fast neutron reactors.
These include Russia’s own BOR-60 research reactor and the operational BN-600 and BN-800 power reactors at the Beloyarsk nuclear power plant.
Fast neutron reactors are a type of nuclear reactor where the chain reaction is sustained by fast neutrons, as opposed to the thermal neutrons used in most commercial reactors.
They often use liquid metals like sodium as a coolant due to sodium’s excellent heat transfer properties and the fact that it does not significantly slow down neutrons.
Notably, Rosatom indicated that this technology could see its first practical application in Kazakhstan, where the decommissioning of the BN-350 fast neutron reactor in Aktau is currently underway.
“Our development can be used for the first time during the decommissioning of the BN-350 sodium-cooled reactor in Aktau, Kazakhstan. This reactor facility contains 680 cubic meters of sodium, which can be transferred to a safe state in three to four years without building a new storage facility, using only the existing capacity,” added Eduard Nikitin, Director for Decommissioning of Nuclear Facilities and Radioactive Waste Management (RW) at TVEL.
Testing the technology for “nuclear backend”
TVEL, as the sole supplier of nuclear fuel for Russian Nuclear Power Plants (NPPs) and a significant global player in nuclear fuel supply, has been actively expanding its role in the “nuclear backend.”
Since 2019, it has served as an industry integrator in the decommissioning of nuclear and radiation-hazardous facilities and the management of associated radioactive waste.
This “nuclear backend” strategy encompasses the safe handling of radioactive waste, spent nuclear fuel, and the decommissioning of end-of-life nuclear facilities, followed by the rehabilitation of contaminated areas for future economic use.
The “Mineral 100/150” plant’s solid-phase oxidation technology is recognized within the Commonwealth of Independent States (CIS) and meets contemporary water resistance standards for final waste disposal.
Andrey Lebezov, General Director of JSC SSC RF – IPPE, highlighted the successful testing of the pilot industrial installation, “Mineral-100/150,” in March 2024.
He affirmed that these tests “confirm the possibility of scaling up the solid-phase oxidation technology and its application in preparation for decommissioning of nuclear facilities with sodium coolant.”
