Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT) (방사성폐기물학회지)

Korean Radioactive Waste Society (한국방사성폐기물학회)
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Verification of Graphite Isotope Ratio Method Combined With Polynomial Regression for the Estimation of Cumulative Plutonium Production in a Graphite-Moderated Reactor

  • Received : 2021.09.17
  • Accepted : 2021.10.19
  • Published : 2021.12.30
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Abstract

Graphite Isotope Ratio Method (GIRM) can be used to estimate plutonium production in a graphite-moderated reactor. This study presents verification results for the GIRM combined with a 3-D polynomial regression function to estimate cumulative plutonium production in a graphite-moderated reactor. Using the 3-D Monte-Carlo method, verification was done by comparing the cumulative plutonium production with the GIRM. The GIRM can estimate plutonium production for specific sampling points using a function that is based on an isotope ratio of impurity elements. In this study, the 10B/11B isotope ratio was chosen and calculated for sampling points. Then, 3-D polynomial regression was used to derive a function that represents a whole core cumulative plutonium production map. To verify the accuracy of the GIRM with polynomial regression, the reference value of plutonium production was calculated using a Monte-Carlo code, MCS, up to 4250 days of depletion. Moreover, the amount of plutonium produced in certain axial layers and fuel pins at 1250, 2250, and 3250 days of depletion was obtained and used for additional verification. As a result, the difference in the total cumulative plutonium production based on the MCS and GIRM results was found below 3.1% with regard to the root mean square (RMS) error.

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Acknowledgement

This work was supported by a 2-Year Research Grant of Pusan National University.

References

  1. J.P. McNeece, B.D. Reid, and T.W. Wood. The Graphite Isotope Ratio Method (GIRM): A Plutonium Production Verification Tool, Pacific Northwest National Laboratory Technical Report, PNNL-12095 (1999).
  2. B.D. Reid, W.C. Morgan, E.F. Love, Jr, D.C. Gerlach, S.L. Petersen, J.V. Livingston, L.R. Greenwood, and J.P. McNeece. Graphite Isotope Ratio Method Development Report: Irradiation Test Demonstration of Uranium as a Low Fluence Indicator, Pacific Northwest National Laboratory Technical Report, PNNL-13056 (1999).
  3. J. Han, J. Jang, and H.C. Lee, "A Suitability Study on the Indicator Isotope for Graphite Isotope Ratio Method (GIRM)", J. Nucl. Fuel Cycle Waste Technol., 18(1), 83-90 (2020). https://doi.org/10.7733/jnfcwt.2020.18.1.83
  4. J. Kang, "Using the Graphite Isotope Ratio Method to Verify the DPRK's Plutonium-Production Declaration," Sci. Glob. Secur., 19, 121-129 (2011). https://doi.org/10.1080/08929882.2011.586309
  5. S. E. Jensen and E. Nonboel. Description of the Magnox Type of Gas Cooled Reactor (MAGNOX), Riso National Laboratory Technical Report, NKS-2 (1999).
  6. H. Lee, W. Kim, P. Zhang, M. Lemaire, A. Khassenov, J. Yu, Y. Jo, J. Park, and D. Lee, "MCS - A Monte Carlo Particle Transport Code for Large-Scale Power Reactor Analysis", Ann. Nucl. Energy, 139, 107276 (2020). https://doi.org/10.1016/j.anucene.2019.107276
  7. C. Braun, S. Hecker, C. Lawrence, and P. Papadiamantis, "North Korean Nuclear Facilities After the Agreed Framework," Center for International Security and Cooperation, Stanford University (2016).