Nuclear Engineering and Technology

Korean Nuclear Society (한국원자력학회)
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An analytical model to decompose mass transfer and chemical process contributions to molecular iodine release from aqueous phase under severe accident conditions

  • Received : 2023.03.31
  • Accepted : 2023.10.21
  • Published : 2024.02.25
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Abstract

Radioactive iodine is a representative fission product to be quantified for the safety assessment of nuclear facilities. In integral severe accident analysis codes, the iodine behavior is usually described by a multi-physical model of iodine chemistry in aqueous phase under radiation field and mass transfer through gas-liquid interface. The focus of studies on iodine source term evaluations using the combination approach is usually put on the chemical aspect, but each contribution to the iodine amount released to the environment has not been decomposed so far. In this study, we attempted the decomposition by revising the two-film theory of molecular-iodine mass transfer. The model involves an effective overall mass transfer coefficient to consider the iodine chemistry. The decomposition was performed by regarding the coefficient as a product of two functions of pH and the overall mass transfer coefficient for molecular iodine. The procedure was applied to the EPICUR experiment and suppression chamber in BWR.

Keywords

Acknowledgement

The authors wish to thank the reviewers on all the peer-review processes for their careful reading of the manuscript and a lot of valuable comments on revising the manuscript from different standpoints. The authors are grateful to several members of SA Research group, Nuclear Safety Research Center, JAEA for the fruitful discussion on the fission product chemistry and transport and helpful comments on this study.

References

  1. B. Clement, L. Cantrel, G. Ducros, F. Funke, L. Herranz, A. Rydl, G. Weber, J. C. Wren, State of the Art Report on Iodine Chemistry, Nuclear Energy Agency, 2007. 
  2. S. Guntay, R. Cripp, IMPAIR/3: a computer program to analyze the iodine behaviour in multi-Compartments of a LWR containment, PSI-Bericht 128 (September 1992). 
  3. K. Moriyama, Y. Maruyama, H. Nakamura, Kiche: A Simulation Tool for Kinetics of Iodine Chemistry in the Containment of Light Water Reactors under Severe Accident Conditions (Contract Research), JAEA-Data/Code 2010-034, 2011. 
  4. J.C. Wren, J.M. Ball, LIRIC 3.2 an updated model for iodine behaviour in the presence of organic impurities, Radiat. Phys. Chem. 60 (2001) 577-596. 
  5. L. Bosland, L. Cantrel, N. Girault, B. Clement, Modeling of iodine radiochemistry in the ASTEC severe accident code: description and application to FPT-2 PHEBUS test, Nucl. Technol. 171 (2010) 88-107. 
  6. A.L. Wright, Primary System Fission Product Release and Transport, U.S. NRC, 1994, https://doi.org/10.2172/10161670. 
  7. E.C. Beahm, C.F. Weber, T.S. Kress, G.W. Parker, Iodine Chemical Forms in LWR Severe Accidents. Final Report, 1992, https://doi.org/10.2172/10142876. 
  8. J.C. Wren, J.M. Ball, G.A. Glowa, The chemistry of iodine in containment, Nucl. Technol. 129 (2000) 297-325. 
  9. J. Ishikawa, K. Kawaguchi, Y. Maruyama, Analysis for iodine release from unit 3 of Fukushima Dai-ichi nuclear power plant with consideration of water phase iodine chemistry, J. Nucl. Sci. Technol. 52 (2015) 308-314. 
  10. T. Ohkura, T. Oishi, M. Taki, Y. Shibanuma, M. Kikuchi, H. Akino, Y. Kikuta, M. Kawasaki, J. Saegusa, M. Tsutsumi, H. Ogose, S. Tamura, T. Sawahata, Emergency Monitoring of Environmental Radiation and Atmospheric Radionuclides at Nuclear Science Research Institute, JAEA Following the Accident of Fukushima Daiichi Nuclear Power Plant, JAEA-Data/Code 2012-010, 2012. 
  11. L.S. Lebel, R.S. Dickson, G.A. Glowa, Radioiodine in the atmosphere after the Fukushima Dai-ichi nuclear accident, J. Environ. Radioact. 151 (2016) 82-93. 
  12. S. Dickinson, F. Andreo, T. Karkela, J. Ball, L. Bosland, L. Cantrel, F. Funke, N. Girault, J. Holm, S. Guilbert, L.E. Herranz, C. Housiadas, G. Ducros, C. Mun, J. C. Sabroux, G. Weber, Recent advances on containment iodine chemistry, Prog. Nucl. Energy 52 (2010) 128-135. 
  13. N. Girault, L. Bosland, S. Dickinson, F. Funke, S. Guntay, L.E. Herranz, D. Powers, LWR severe accident simulation: iodine behaviour in FPT2 experiment and advances on containment iodine chemistry, Nucl. Eng. Des. 243 (2012) 371-392. 
  14. S. Gupta, E. Schmidt, B. von Laufenberg, M. Freitag, G. Poss, F. Funke, G. Weber, Thai test facility for experimental research on hydrogen and fission product behaviour in light water reactor containments, Nucl. Eng. Des. 294 (2015) 183-201. 
  15. G. Weber, L.E. Herranz, M. Bendiab, J. Fontanet, F. Funke, B. Gonfiotti, I. Ivanov, S. Krajewski, A. Manfredini, S. Paci, M. Pelzer, T. Sevon, Thermal-hydraulic-iodine chemistry coupling: insights gained from the SARNET benchmark on the Thai experiments Iod-11 and Iod-12, Nucl. Eng. Des. 265 (2013) 95-107. 
  16. K. Fischer, G. Weber, F. Funke, G. Langrock, Experimental determination and analysis of iodine mass transfer coefficients from Thai test Iod-23, in: 5th European Review Meeting on Severe Accident Research, ERMSAR, Cologne, Germany, March, 2012, pp. 21-23. 
  17. S. Dickinson, H.E. Sims, Development of the INSPECT model for the prediction of iodine volatility from irradiated solutions, Nucl. Technol. 129 (2000) 374-386. 
  18. K. Fischer, M. Freitag, H.S. Kang, Mechanistic model of iodine mass transfer at pool surfaces, Nucl. Eng. Des. 278 (2014) 627-631. 
  19. L.E. Herranz, J. Fontanet, L. Cantrel, Modeling liquid-gas iodine mass transfer under evaporative conditions during severe accidents, Nucl. Eng. Des. 239 (2009) 728-734. 
  20. L. Cantrel, P. March, Mass transfer modeling with and without evaporation for iodine chemistry in the case of a severe accident, Nucl. Technol. 154 (2006) 170-185. 
  21. L. Bosland, S. Dickinson, G.A. Glowa, L.E. Herranz, H.C. Kim, D.A. Powers, M. Salay, S. Tietze, Iodine-paint interactions during nuclear reactor severe accidents, Ann. Nucl. Energy 74 (2014) 184-199. 
  22. K. Moriyama, S. Tashiro, N. Chiba, F. Hirayama, Y. Maruyama, H. Nakamura, A. Watanabe, Experiments on the release of gaseous iodine from gamma-irradiated aqueous CsI solution and influence of oxygen and methyl isobutyl ketone (MIBK), J. Nucl. Sci. Technol. 47 (2010) 229-237. 
  23. S. Guentay, R.C. Cripps, B. Jackel, H. Bruchertseifer, Iodine behaviour during a severe accident in a nuclear power plant, Chimia 59 (2005) 957-965. 
  24. I. Lengyel, I.R. Epstein, K. Kustin, Kinetics of iodine hydrolysis, Inorg. Chem. 32 (1993) 5880-5882. 
  25. K. Ishigure, H. Shiraishi, Factors affecting radiolysis of dilute iodine solutions, in: A.C. Vikis (Ed.), Proceedings of the Second CSNI Workshop on Iodine Chemistry in Reactor Safety, OECD, 1989, pp. 39-47. https://inis.iaea.org/collection/NCLCollectionStore/_Public/22/068/22068932.pdf. 
  26. C.-C. Lin, Chemical effects of gamma radiation on iodine in aqueous solutions, J. Inorg. Nucl. Chem. 42 (1980) 1101-1107. 
  27. C.B. Ashmore, J.R. Gwyther, H.E. Sims, Some effects of pH on inorganic iodine volatility in containment, Nucl. Eng. Des. 166 (1996) 347-355. 
  28. F. Taghipour, G.J. Evans, Iodine behavior under conditions relating to nuclear reactor accidents, Nucl. Technol. 137 (2017) 181-193. 
  29. G.J. Evans, Measurement and modeling of iodine volatility above irradiated Csl solutions, Nucl. Technol. 116 (1996) 293-305. 
  30. C.-C. Lin, J.-H. Chao, Reassessment of reactor coolant and iodine chemistry under accident conditions, J. Nucl. Sci. Technol. 46 (2009) 1023-1031. 
  31. W.G. Whitman, The two-film theory of gas absorption, Chem. Metall. Eng. 29 (1923) 146-148. 
  32. J.R. Ling, Enhancement of the Interfacial Transfer of Iodine by Chemical Reaction, Diss. University of Toronto, 1997. https://www.nlc-bnc.ca/obj/s4/f2/dsk2/ftp01/MQ29382.pdf. 
  33. L.L. Humphries, B.A. Beeny, F. Gelbard, D.L. Louie, J. Phillips, MELCOR Computer Code Manuals Vol. 1: Primer and Users' Guide, Version 2.2. 9541 2017, 2017. 
  34. J. Ball, G. Glowa, C. Wren, A. Rydl, C. Poletiko, Y. Billarand, F. Ewig, F. Funke, A. Hidaka, R. Gauntt, International Standard Problem (ISP) N 41-Containment Iodine Computer Code Exercise Based on a Radioiodine Test Facility (RTF) Experiment: NEA, NEA/CSNI/R (2000), 2000, p. 6. 
  35. OECD/NEA, Information Portal for the Fukushima Daiichi Accident Analysis and Decommissioning Activities, 2016. https://fdada.info/en/home2. 
  36. P.C. Owczarski, K.W. Burk, SPARC-90: A Code for Calculating Fission Product Capture in Suppression Pools, Richland, WA, NUREG/CR-5765 PNL-7732, 1991. 
  37. L.F. Parsly, Design Considerations of Reactor Containment Spray Systems. Part VII. A Method for Calculating Iodine Removal by Sprays, No. ORNL-TM-2412 (PT. 7)), Oak Ridge National Lab, 1970. 
  38. S. Guilbert, L. Bosland, D. Jacquemain, B. Clement, F. Andreo, G. Ducros, S. Dickinson, L. Herranz, J. Ball, Radiolytic oxidation of iodine in the containment at high temperature and dose rate, in: International Conference Nuclear Energy for New Europe 2007, Portoroz, Slovenia, 2007. https://www.osti.gov/etdeweb/servlets/purl/21083809. 
  39. G.J. Evans, J.R. Ling, Enhancement of the interfacial transfer of iodine by chemical reaction, Can. J. Chem. Eng. 78 (2000) 221-225. 
  40. J. Kalilainen, T. Lind, Uncertainty quantification study on gas phase iodine release from Fukushima Daiichi accident in unit 3, Ann. Nucl. Energy 166 (2022), 108740. 
  41. K. Nanjo, J. Ishikawa, T. Sugiyama, M. Pellegrini, K. Okamoto, Revolatilization of iodine by bubbly flow in the suppression pool during an accident, J. Nucl. Sci. Technol. 59 (2022) 1407-1416. 
  42. When JAEA participated in the OECD/NEA ISP-41 project, the IODICL code was utilized. Based on the code, the KICHE code has been developed (Ref. [3]) and has been applied to RTF and ISP-41 experiments. Although the simulation results are provided using dataset 10a, the reactions of inorganic iodine species listed in the dataset are quite similar to the LIRIC dataset. The KICHE code used in this study is almost the same as the original (at least, the numerical solver is the same).