Radiation Physics and Engineering
A peer-reviewed journal published by K. N. Toosi University of Technology

Uncertainty investigation of Cs-134/Cs-137 activity ratio method in determination of the spent nuclear fuel burnup

Document Type : Research Article

Authors

Zohreh Gholamzadeh
Atiyeh Jozvaziri

Safety and Nuclear Research Reactor School, Nuclear Science and Technology Research Institute, Tehran, Iran

https://doi.org/10.22034/rpe.2025.500121.1263
Abstract
For storage of a spent fuel during the life of the facility, testing or evaluation may be required to determine the integrity of the spent fuel. In addition, various tests of the spent fuel are carried out at nuclear facilities for many purposes. Therefore, it is necessary to theoretically and experimentally evaluate the fuel burnups as one of the most important issues for nuclear spent fuel storage. The present study discusses the 134Cs/137Cs activity ratio method in determination of the spent nuclear fuel burnup, which is very important in view of the spent fuel storage as well as its dose rate calculation. For this aim, ORIGEN and MCNPX codes were used to calculate the radioisotopes' concentrations during the nuclear fuel burnup and different cooling times of Tehran Research Reactor (TRR) fuel assembly. The obtained results showed the burnup estimation might be maximum 2 times different from its real value by using this method if the fuel burnup history has not been regarded and the cooling time is unknown. For the specific cooling times, the discrepancy may be 36% if the fuel burnup history has not been modelled. The discrepancies between the estimated burnup and the real value may be less if the TRR fuel assembly burnups are less than 55%.

Highlights

  • Fuel burnup determination is mandatory for spent fuel storage.
  • 134Cs/137Cs activity ratio is a common method for SF burnup determination.
  • ORIGEN code could be used to calculate 134Cs/137Cs activity ratio.

Keywords

Spent nuclear fuel
134Cs /137Cs ratio
Burnup
ORIGEN code

 

Copyright
RPE is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License (CC BY-NC 4.0).

Conflict of Interest

‎The authors declare no potential conflict of interest regarding the publication of this work‎.

Funding

‎The authors declare that no funds‎, ‎grants‎, ‎or other financial support were received during the preparation of this manuscript‎.

 

 
Caruso, S., Murphy, M., Jatuff, F., et al. (2007). Validation of 134Cs, 137Cs and 154Eu single ratios as burnup monitors for ultra-high burnup UO2 fuel. Annals of Nuclear Energy, 34(1-2):28–35.
Croff, A. G. (1980). User’s manual for the ORIGEN2 computer code. Technical report, Oak Ridge National Lab.
Ezure, H. (1990). Calculation of atom ratios of 134Cs/137Cs, 154Eu/137Cs and Pu/U, burnup and most probable production amount of plutonium in fuel assemblies of JPDR-1. Journal of nuclear science and technology, 27(6):562–571.
Fensin, M. L. (2008). Development of the MCNPX depletion capability: A Monte Carlo linked depletion method that automates the coupling between MCNPX and CINDER90 for high fidelity burnup calculations. University of Florida.
Harp, J. M., Demkowicz, P. A., Winston, P. L., et al. (2014). An analysis of nuclear fuel burnup in the AGR-1 TRISO fuel experiment using gamma spectrometry, mass spectrometry, and computational simulation techniques. Nuclear Engineering and Design, 278:395–405.
Joshi, J., Trahan, A. C., and Charlton, W. (2019). Absolute Measurement of 137Cs and 134Cs/137Cs and 154Eu/137Cs Ratios to Verify University of Texas TRIGA Reactor Spent Fuel BU. Technical report, Los Alamos National Laboratory (LANL), Los Alamos, NM (United States).
Min, D., Park, H., Park, K., et al. (1999). Determination of burnup, cooling time and initial enrichment of PWR spent fuel by use of gamma-ray activity ratios.
Mirvakili, S., Keyvani, M., Arshi, S. S., et al. (2012). Possibility evaluation of eliminating the saturated control fuel element from Tehran research reactor core. Nuclear Engineering and Design, 248:197–205.
Oleinik, S., Maksimov, M., and Maslov, O. (2002). Determination of the burnup of spent nuclear fuel during reloading. Atomic Energy, 92(4):296–300.
Park, K.-J., Ju, J.-S., Shin, H.-S., et al. (2009). Determination of the Burnup and Pu/U Ratio of PWR Spent Fuel Samples by a Gamma-ray Spectrometry. In Proceedings of the KNS spring meeting, Nucl. Eng. & Tech, volume 41, page 10.
Pelowitz, D. B. et al. (2005). MCNPXTM user’s manual. Los Alamos National Laboratory, Los Alamos, 5:369.
Shin, H., Lee, S.-Y., Ro, S.-G., et al. (2002). Non-destructive burnup determination of PWR spent fuel using Cs-134/Cs-137 and Eu-154/Cs-137.
Radiation Physics and Engineering
Volume 6, Issue 4
Autumn 2025
Pages 17-22

  • Receive Date 15 January 2025
  • Revise Date 26 February 2025
  • Accept Date 26 April 2025

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