Russia proposes optical laser monitoring method for spent nuclear fuel reprocessing

Recently, a research team from Sechenov University in Russia, together with the “Proryv” Project (Proryv Project) and the All-Russian Scientific Research Institute of Inorganic Materials (VNIINM), published latest results in the journal Applied Spectroscopy, proposing a non-contact optical method for continuous monitoring of the spent nuclear fuel reprocessing process.

It is reported that in the liquid-liquid extraction process of spent nuclear fuel reprocessing, traditional laboratory analysis has problems such as long sampling time and increased risk of radioactive waste. The research team introduced Raman Spectroscopy to monitor the state of extractants such as tributyl phosphate in the organic phase, with a median error of about 1%; meanwhile, laser-induced breakdown spectroscopy (LIBS) was used to determine the concentration of metal elements in the aqueous phase, with an average error controlled at 4%–8%, achieving near-real-time synchronous monitoring of the two-phase streams.

Gleb Budylin, head of the Laboratory of Clinical Biophotonics at Sechenov University, pointed out that the core advantage of this technology lies in the absence of need for adding reagents or performing complex sample preparation. In the future, high-value measurement modules can be placed outside high-radiation areas, with only the measurement cell retained in the process pipeline, thereby greatly reducing the frequency of manual sampling and quickly detecting process deviations.

At present, the technology has completed feasibility verification in simplified model solutions in the laboratory. With the advancement of Russia’s “Proryv” closed fuel cycle project, the research team will next verify the method in complex multi-component and high-irradiation environments, and promote remote adaptation of the equipment, laying the foundation for automated control of industrial-scale spent nuclear fuel reprocessing.