Optimization of radiation protection of containers for solidified liquid radioactive waste

Solving the problem of environmentally safe management of radioactive waste in addition to ensuring the safe operation of nuclear power plants is a main condition for the acceptability of nuclear power as a reliable source of electricity. The problem of liquid radioactive waste management is updated. The ion-selective purification method was chosen as the optimal option for liquid radioactive waste for final isolation of conditioned RW has been substantiated. High efficiency of new generation inorganic sorbents increases the efficiency of ion-selective sorption units provided that the problem of safe storage of spent medium and high activity sorbent in places of processing, transportation and burial is solved. In this connection, an important condition for realization of this technology is optimization of radiation protection of a container with radioactive waste. The task on optimization of the effective dose received from the spent filter-container is specified. The structure and dimensions of the container are stipulated. The protective materials for the inner capsule and the outer protective coating, as well as the material of the filler located between the capsule and the container shell are selected. Monte Carlo (MC) simulations with an input value of F6 and six detectors on each side of the container were performed to predict the released energy at a distance of 1 m from the outer shell of the container. The results of the analysis of the effect of the radioactive waste capsule material and its wall thickness, the type of the filler and its thickness on the radiation protection characteristics of the container are presented. Isotopes 137Cs and 60Co in concentrations of 90% and 10% respectively were chosen as solid RAW filling the container. Dependence of allocated energy, equivalent dose, changes in transmittance and radiation shielding coefficients on the material and thickness of the receiving capsule were obtained based on simulation results. Conclusions on the optimal parameters of the filter-container are formulated and the advantages of the investigated solutions are substantiated.

1. Novikov G.A. Obespechenie bezopasnosti v oblasti ispol'zovaniya atomnoi ehnergii: uchebnik / G.A. Novikov, O.L. Tashlykov, S.E. Shcheklein; pod obshch. red. G.A. Novikova. – Ekaterinburg : Izd-vo Ural. Un-ta, 2017. – 552 s.

2. Tashlykov O.L. Ehkspluatatsiya i remont yadernykh paroproizvodyashchikh ustanovok AEHS: uchebnik / O.L.Tashlykov [i dr.]. V 2 kn. –M.: Ehnergoatomizdat, – 1995. – Kn.1 – 256 s.

3. Tashlykov O.L. O probleme snizheniya dozovykh zatrat personala AEHS / O.L. Tashlykov, S.E. Shchekle-in, V.I. Bulatov // Izvestiya vuzov. Yadernaya ehnerge-tika. – 2011. – №1. – S.55-60.

4. Pererabotka i konditsionirovanie RAO na AEHS dlya podgotovki k okonchatel'noi izolyatsii / M.R. Stakhiv [i dr.]. – M.: VNIIAEHS. 2013/ https://www.atomic-energy.ru/technology/40756.

5. Nosov YU.V. Osobennosti vyvoda iz ehkspluatatsii bystrykh reaktorov BN-350, -600 / YU.V. Nosov [i dr.] // Atomnaya ehnergiya. 2018. T. 125. № 4. S. 195-199.

6. Remez V.P. Povyshenie Ehffektivnosti lokalizatsii radionuklidov kobal't-60 i tsezii-137 iz zhidkikh radioaktivnykh otkhodov v reshenii proble-my obespecheniya radiatsionnoi bezopasnosti AEHS / Remez V.P. [i dr.] // Yadernaya fizika i inzhiniring. – 2016. – Tom 7. – № 2. – S. 129–137.

7. Arustamov A. EH. Metod ionoselektivnoi ochistki zhidkikh radioaktivnykh otkhodov atomnykh stantsii / Arustamov A. EH. [i dr.] // Bezopasnost' zhiznedeyatel'nosti. – 2005. – №11. – S. 13 – 16.

8. Litovchenko V.YU. Ispol'zovanie metoda Monte-Karlo dlya optimizatsii sostava radiatsionnoi zashchity konteinerov dlya razmeshcheniya konditsionirovannykh zhidkikh otkhodov / V.YU. Litovchenko [i dr.] // Fizika. Tekhnologii. Innovatsii : sbornik statei VIII Mezhdunarodnoi molodezhnoi nauchnoi konfe-rentsii. – Ekaterinburg: URFU, 2021. S. 426-437.

9. NP-093-14. Kriterii priemlemosti radioaktivnykh otkhodov dlya zakhoroneniya (v red. prikaza Ro-stekhnadzora ot 17 noyabrya 2017 g. № 481). – M.: FBU «NTTS YARB», 2017. 36 s.

10. Tashlykov O. L. Ion-selective treatment as a method for increasing the efficiency of liquid radioactive waste reducing in accordance with acceptance criteria for disposal / O. L. Tashlykov [i dr.] // AIP Conference Proceedings, 2021, 2388(1):020032.

11. Bulatov V.I. Sooruzhenie kompleksa pererabotki zhidkikh radioaktivnykh otkhodov na Beloyarskoi AEHS / V.I. Bulatov, A.O. Tashlykov, O.L. Tashlykov // Mezhdunarodnyi nauchnyi zhurnal Al'ternativnaya ehnergetika i ehkologiya. – 2020. – № 25-27 (347-349). – S.62-72.

12. Litovchenko V. YU. Raschetnoe obosnovanie ra-diatsionnykh parametrov zashchitnogo konteinera s tsementnym kompaundom, soderzhashchim sorbent s izo-topami tseziya-137 i kobal'ta-60 / V. YU. Litovchenko, N. A. Vasyutin, O. L. Tashlykov // Yadernye tekhno-logii: ot issledovanii k vnedreniyu – 2019: Sbornik materialov nauchno-prakticheskoi konferentsii - Nizhnii Novgorod, – 2019. – S. 85–86.

13. Tashlykov O.L. Ehksperimental'noe issledovanie zashchit ot gamma-izlucheniya organo-metallicheskikh kompozitsii / O.L. Tashlykov [i dr.] // Global'naya yadernaya bezopasnost'. – 2015. – № 2 (15). – S. 49-55.

14. Modelirovanie radiatsionnoi zashchity konteinerov dlya transportirovki vysokoehnergetiche-skikh beta-istochnikov / V. YU. Litovchenko [i dr.] // Voprosy atomnoi nauki i tekhniki. Ser. Materialovedenie i novye materialy. – 2019. – Vyp. 5(101). – S. 4–12.

15. Mahmoud K.A. Investigation of radiation shield-ing properties for some building materials rein-forced by basalt powder / K.A. Mahmoud [et al.] . December 2019. AIP Conference Proceedings 2174(1): 020036.

16. Mahmoud K.A. Gamma ray shielding characteristics and exposure buildup factor for some natural rocks using MCNP-5 code / K.A. Mahmoud, M.I. Sayyed, O.L. Tashlykov // Nuclear Engineering and Technology. 51 (2019) – Rr.1835-1841.

17. Mikhailova A. F. Puti realizatsii printsipa optimizatsii v radiologicheskoi zashchite personala / A. F. Mikhailova, O. L. Tashlykov // Yadernaya fizika i inzhiniring. – 2018. – Tom 9. – № 4. – S. 393-401.

18. Samoilov A.A. Prioritetnye napravleniya optimizatsii obrashcheniya s radioaktivnymi otkhodam / A.A. Samoilov, S.V. Strizhova, P.A. Blokhin // Plenarnye i sektsionnye doklady XI mezhdunarodnoi nauchno-tekhnicheskoi konferentsii Bezopasnost', ehffektivnost' i ehkonomika atomnoi ehnergetiki. – Moskva: AO «Kontsern RosehnergoatoM», – 2018. – S.269-275.

19. Tashlykov O.L. Raschetno-ehksperimental'noe issledovanie mestnykh mineralov i kompozitsii na ikh osnove dlya sozdaniya radiatsionnykh zashchit khranilishch radioaktivnykh otkhodov AEHS / O.L. Tashlykov, K.A.G. Makhmud // Mezhdunarodnyi nauchnyi zhurnal Al'ternativnaya ehnergetika i ehkologiya. – 2020. – № 28-30 (350-352). – S. 57-66.

20. Mahmoud K.A. Comparative studies between the shielding parameters of concretes with different additive aggregates using MCNP-5 simulation code / K.A. Mahmoud, M.I. Sayyed, O.L. Tashlykov // Radiation Physics and Chemistry – 2019. – Vol. 165. Nomer stat'i 108426.

21. Tashlykov O.L. Improvement in the design of shielding containers for intermediate-level radioactive waste / O.L Tashlykov [et al.] // Radiation Physics and Chemistry, 2022, 110229.

22. Litovchenko V. Yu. Using the Monte-Carlo method to optimize the radiation protection composition of containers for storing conditioned liquid waste / V. Yu. Litovchenko [et al.] // AIP Conference Proceedings 2466, 020005 (2022).