EDN: MVCQWY
Authors & Affiliations
Evtushenko E.A.1, Kascheev M.V.2, Levchenko V.A.2, Shovikov A.V.1
1 Branch JSC “Concern Rosenergoatom” Leningrad Nuclear Power Station, Sosnovy Bor, Russia
2 The Limited Liability Company “Simulation Systems Ltd.”, Obninsk, Russia
Evtushenko E.A.1 – Deputy Head of the Radiation Safety Department (for Operation).
Shovikov A.V.1 – Radiation Protection Technician of the Radiation Safety Department.
Kascheev M.V.2 – Chief Researcher, Dr. Sci. (Tech.). Contacts: 133, Lenin Avenue, Obninsk, Kaluga region, Russia, 249035. Tel.: +7 (48439) 6-03-61; e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it..
Levchenko V.A.2 – Director, Cand. Sci. (Tech.).
Abstract
The article is devoted to the study of the influence of coolant parameters on the radiation situation of the second power unit of LNPP-2 during the shutdown period for planned preventive maintenance. The paper considers the operational experience of domestic VVER reactors and their foreign closest PWR analogues in terms of reducing the concentration of activated corrosion products in the coolant during normal operation and shutdown. The article presents the results of the implementation of a technical solution related to the slow cooling of power unit No. 2 during the shutdown for repair. The protocol of slow cooling is described in stages. To assess the effectiveness of the implemented regime, radionuclide and chemical analysis of the samples of the primary circuit coolant, radiation monitoring at reference points (in the bends of the MCPs under MCPUs, and at the entrance of the equipment room of the special water treatment system) were performed. The results of monitoring the volume activity of the radionuclides in the emissions from the ventilation pipe, as well as the volume activity of the radionuclide Ag-110m in the control tanks during repair in 2024 and 2025, were compared. Based on the results obtained and the experience of implementing slow cooling during the shutdown period before repair in 2025, proposals have been put forward to improve the cooling protocol for subsequent repairs at both LNPP-2 power units.
Keywords
nuclear power plant, radionuclide, VVER-1200, gamma-ray spectrometer, sampling, primary circuit, water chemistry, special water treatment, cooling of the power unit, reactor shutdown
Article Text (PDF, in Russian)
References
- Povarov V.P., Rosnovskiy S.V., Gusev I.N., Men’shikh P.A., Rosnovskaya O.V., Bulka S.K. Radiatsionnaya zashchita energoblokov atomnykh elektrostantsiy proekta “AES-2006” [Radiation Protection of Nuclear Power Plants Units of the AES-2006 Design]. Voronezh, Diamant Publ., 2021. 560 p.
- Roshchektaev B.М. Vodno-khimicheskiy rezhim AES s reaktorami VVER-1000 i RBMK-1000:Uchebnoe posobie [Water chemistry of NPPs with VVER-1000 and RBMK-1000 reactors. Study guide]. Moscow, NIYAU MIFI Publ., 2010. 132 p.
- Yurmanov V.A., Amosov M.M., Mamet V.A. Vodno-khimicheskiy rezhim reaktorov VVER v periody ostanovov energoblokov [Water chemistry of VVER reactors during shutdowns of power units]. Teploenergetika – Thermal Engineering, 1996, no. 8, pp. 7–16.
- Malik J.I., Mirza N.M., Mirza S.M. Time-dependent corrosion product activity in a typical PWR due to changes in coolant chemistry for long-term fuel cycles. Progress in Nuclear Energy, 2012, vol. 58, pp. 100–107.
- Mirza N.M., Rafique M., Hyder M.J., Mirza S.M. Computer simulation of corrosion product activity in primary coolants of a typical PWR under flow rate transients and linearly accelerating corrosion. Annals of Nuclear Energy, 2003, vol. 30, pp. 831–851.
- Deligiannis A. Comparative analysis of source term removal at Cook nuclear plant. Urbana-Champaign, University of Illinois Publ., 2009. 73 p.
- Li C., Meng S., Ruan T., Yan Y. Research of Corrosion Products Migration Behavior in PWR Primary Circuit Under Extended Low Power Operation Mode. Proc. of the 23rd Pacific Basin Nuclear Conference. Beijing & Chengdu, China, 2023, vol. 1,pp. 45–52. DOI: https://doi.org/10.1007/978-981-99-1023-6_5.
- Deeba F., Mirza A.M., Mirza N.M. Modeling and simulation of corrosion product activity in pressurized water reactors under power perturbations. Annals of Nuclear Energy, 1999, vol. 26, pp. 561–578. DOI: https://doi.org/10.1016/S0306-4549(98)00087-5.
- Zhou W., Woller K.B., Zheng G., Stahle P.W., Short M.P. A simultaneous corrosion/irradiation facility for testing molten salt-facing materials. Nuclear Instruments and Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms, 2019, vol. 440, pp. 54–59. DOI: https://doi.org/10.1016/j.nimb.2018.11.024.
- Varga K., Hirschberg G., Nemeth Z., Myburg G., Schunk J., Tilky P. Accumulation of radioactive corrosion products on steel surfaces of VVER-type nuclear reactors. II. 60Co. Journal of Nuclear Materials, 2001, vol. 298, no. 3, pp. 231–238.
- Molinari M., D’onorio M., Mariano G., Terranova N., Caruso G. Water Chemistry Impact on Activated Corrosion Products: An Assessment on Tokamak Reactors. Energies, 2023, vol. 16, no. 12, p. 4726. DOI: https://doi.org/10.3390/en16124726.
- D’Onorio M., Molinari M., Mariano G., Terranova N. RAVEN/OSCAR-Fusion Coupling for Activated Corrosion Products Assessments, Sensitivity, and Uncertainty Quantification. IEEE Transactions on Plasma Science, 2022, vol. 50, no. 11, pp. 4527–4532. DOI: https://doi.org/10.1109/TPS.2022.3187784.
- Lin G., Li F., Fang J., Sun Y. Reduced deposition of 110mAg colloids by improved oxidation operation process during shutdown of a PWR. Journal of Radioanalytical and Nuclear Chemistry, 2022, vol. 331, pp. 111–118. DOI: https://doi.org/10.1007/s10967-021-08109-9.
- Du B., Yu S., Zhao Q., Cheng X., Wei J., Zhao X. The speciation analysis of colloids in the primary coolant in nuclear power plant. Radiation Physics and Chemistry, 2019, vol. 159, pp. 81–88. DOI: https://doi.org/10.1016/j.radphyschem.2019.02.023.
- Povarov V.P., Galanin A.V., Vorob’ev S.A., Litvinova P.V., Karandeeva N.V., Khokhlova M.V., Dronov D.M. Vodno-khimicheskiy rezhim AES-2006: Rukovodstvo dlya organizatsiy i kompaniy, osushchestvlyayushchikh bezopasnoe i effektivnoe vedenie tekhnologicheskikh protsessov pri ekspluatatsii energoblokov atomnykh elektricheskikh stantsiy [Water Сhemistry of AES-2006: A Guide for Organizations and Companies that Carry Out Safe and Efficient Maintenance of Technological Processes During the Operation of Nuclear Power Plants Units]. Voronezh, Diamant Publ., 2022. 627 p.
UDC 621.039.53
Problems of Atomic Science and Technology. Series: Nuclear and Reactor Constants, 2026, no. 2, 2:9
