Scientists from Rosatom’s Fuel Division and the Breakthrough Project have developed an innovative technology for the purification and separation of nuclear materials from irradiated nuclear fuel. The new crystallisation refining technology will be implemented at the module for reprocessing irradiated high-density uranium-plutonium nitride fuel (SNUP) as part of the pilot demonstration power complex (ODEK – Opitno Demonstratsionovo Energo-Kompleks).
The ODEK project is being built at the Siberian Chemical Combine in Seversk as part of the Breakthrough (Proryv) project intended to demonstrate closed fuel cycle technology. It is based on the Brest-OD-300 lead cooled fast reactor supported by the (MFR) and a module for reprocessing irradiated fuel. The reactor is scheduled for grid connection in 2027; the MFR is planned for commissioning this year; construction of the reprocessing unit is planned for 2025-2026 for commissioning in 2030.
The ODEK Processing Module assumes that the crystallisation section will complete the so-called “refining line”, i.e. will become the final technological stage in the chain of purification of nuclear materials isolated from irradiated SNUP fuel – uranium, plutonium and neptunium. Crystallisation refining technology will ensure a high level of safety during used fuel reprocessing. The technological process will allow for the joint purification and separation of uranium, plutonium and neptunium, eliminating the possibility of isolating plutonium as a separate product. Thus, the technology fully complies with the nuclear non-proliferation regime.
Unlike other extraction technologies for purification of nuclear materials, crystallisation results in the production of a smaller volume of secondary waste, in part by using only nitric acid solutions as reagents. This technology will improve the environmental safety of the used fuel reprocessing.
Irradiated fuel reprocessing technologies are of particular importance for closing the nuclear fuel cycle at ODEK. Materials extracted from the used fuel, after processing, will be sent for refabrication (and recycling to produce of fresh fuel. Thus, this system will gradually become almost autonomous and independent of external energy supplies.