An international journal published by K. N. Toosi University of Technology

Document Type : Research Article

Authors

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

Abstract

‎Thorium is more abundant in nature than uranium‎. ‎The fertile thorium fuel can breed to fissile U-233 by absorbing a neutron‎. ‎The produced fissile has good neutronic performance in both thermal and fast neutron spectra‎. ‎Many types of thorium-based fuels were applied in different nuclear reactors‎. ‎Also natural thorium oxide is used as seed/blanket configuration that the ThO2 rods are used in the outer sections of any fuel assembly‎. ‎The present study aims to investigate the ThO2 fuel rod loading in 3000 MW VVER-1000 power reactor‎. ‎MCNPX and ORIGEN codes were used to evaluate its effects on the core neutronic‎. ‎In addition‎, ‎the gamma emission rates of ThO2 spent fuel than the UO2 routine fuel of VVER-1000 was investigated‎. ‎The obtained results of the computational study showed the ThO2 fuel rod loading in some VVER-1000 fuel assemblies would not end to a breeding behavior of the reactor core even after one-year burnup at 3000 MW power‎. ‎However‎, ‎the enriched uranium fuel loading reduction may make a motivation for thorium fuel application in the power reactor‎.

Highlights

• ThO2 fresh fuel loading in VVER-1000 power reactor does not disturb neutronic and safety parameters.

• ThO2 spent fuel of VVER-1000 power reactor suffers higher gamma dose rates than UO2 spent fuel.

• ThO2 fuel rod loading in VVER-1000 increases cycle lengths but will not result in breeding behavior.

Keywords

Bobrov, E., Alekseev, P., Chibinyaev, A., et al. (2016). The choice of the fuel assembly for VVER-1000 in a closed fuel cycle based on REMIX-technology. EPJ Nuclear Sciences and Technologies, 2:42.

Breza, J., Daˇr´ılek, P., and Neˇcas, V. (2010). Study of thorium advanced fuel cycle utilization in light water reactor VVER-440. Annals of Nuclear Energy, 37(5):685–690.

Briesmeister, J. F. et al. (2000). MCNPTM-A general Monte Carlo N-particle transport code. Version 4C, LA-13709-M, Los Alamos National Laboratory, 2.

Croff, A. G. (1980). User’s manual for the ORIGEN2 computer code. Technical report, Oak Ridge National Lab. 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. Frybort, J. (2014a). Comparison of the radiological hazard of thorium and uranium spent fuels from VVER-1000 reactor. Radiation Physics and Chemistry, 104:408–413.

Frybort, J. (2014b). Equilibrium thorium fuel loading in VVER-1000 reactor. In Proceedings of the 2014 15th International Scientific Conference on Electric Power Engineering (EPE), pages 693–697. IEEE.

FSAR (2007). Final Safety Analysis Report (FSAR) of the BNPP-1, Reactor. Technical report.

Fukaya, Y. (2015). Development of simple method to incorporate out-of-core cooling effect on thorium conversion in multipass fueled reactor and investigation on characteristics of the effect. Annals of Nuclear Energy, 81:301–305.

Galahom, A. A. (2019). Improvement of the VVER-1200 fuel cycle by introducing thorium with different fissile material in blanket-seed assembly. Nuclear Science and Engineering, 193(6):638–651.

Gallmeier, F. X., Ferguson, P. D., Lu, W., et al. (2010). The CINDER’90 transmutation code package for use in accelerator applications in combination with MCNPX. Technical report, Oak Ridge National Lab.(ORNL), Oak Ridge, TN (United States). Spallation.

Gholamzadeh, Z., Gholshanian, M., and Mirvakili, S. M. (2020a). Tho2 spent fuel assemblys gamma dose rate dependency to burnup and cooling time. Radiation Physics and Engineering, 1(3):43–48.

Gholamzadeh, Z., Gholshanian, M., and Mirvakili, S. M. (2020b). Tho2 spent fuel assemblys gamma dose rate dependency to burnup and cooling time. Radiation Physics and Engineering, 1(3):43–48.

Gholamzadeh, Z., Mirvakili, S., and Feghhi, S. (2015). Neutronic performance of (Reprocessed U/Th)O2 fuel in CANDU 6 reactor. Kerntechnik, 80(3):263–269.

Hassanzadeh, M., Feghhi, S., and Khalafi, H. (2013). Calculation of kinetic parameters in an accelerator driven subcritical TRIGA reactor using MCNIC method. Annals of Nuclear Energy, 59:188–193.

Jeong, C. J., Park, C. J., and Ko, W. I. (2008). Dynamic analysis of a thorium fuel cycle in CANDU reactors. Annals of Nuclear Energy, 35(10):1842–1848.

Korkmaz, M. E., Agar, O., and B¨uy¨uker, E. (2014). Burnup analysis of the VVER-1000 reactor using thorium-based fuel. Kerntechnik, 79(6):478–483.

Li, X., Cai, X., Jiang, D., et al. (2015). Analysis of thorium and uranium based nuclear fuel options in Fluoride saltcooled High-temperature Reactor. Progress in Nuclear Energy, 78:285–290.

Liu, L., Zhang, D., Lu, Q., et al. (2016). Preliminary neutronic and thermal-hydraulic analysis of a 2 MW thoriumbased molten salt reactor with solid fuel. Progress in Nuclear Energy, 86:1–10.

Mirvakili, S. M., Gholamzadeh, Z., and Feghhi, S. A. H. (2016). Computational analysis of neutronic effects of ThO2 rods loaded in CANDU 6 fuel assemblies. Nuclear Science and Techniques, 27(4):79.

Pelowitz, D. et al. (2013). Mcnp6 Users Manual (Los Alamos National Laboratory). LACP-00634, May.

Persson, C.-M. (2005). Reactivity determination and Monte Carlo simulation of the subcritical reactor experiment–Yalina. Department of Nuclear and Reactor Physics, Royal Institute of Technology, Stockholm, 16.

Rachamin, R., Fridman, E., and Galperin, A. (2015). Feasibility assessment of the once through thorium fuel cycle for the PTVM LWR concept. Annals of Nuclear Energy, 85:1119–1130.

Rosenstock, W. and Schumann, O. (2013). Thorium for nuclear energy-a proliferation risk? Verhandlungen der Deutschen Physikalischen Gesellschaft.

S¸ahin, S., Yıldız, K., and Acır, A. (2004). Power flattening in the fuel bundle of a CANDU reactor. Nuclear Engineering and Design, 232(1):7–18.

S¸ahin, S., Yıldız, K., S¸ahin, H. M., et al. (2006). Investigation of CANDU reactors as a thorium burner. Energy Conversion and Management, 47(13-14):1661–1675.

Shirazi, M. (1996). Thermal-hidraolyc study of TRR core in fuel conversion frome highly enriched uranium to low enriched uranium fuel. International Journal of Engineering, 9(2):45–52.

Vu, T. M. and Kitada, T. (2015). Seed and blanket ads using thorium–reprocessed fuel: Parametric survey on TRU transmutation performance and safety characteristics. Annals of Nuclear Energy, 78:176–179.

Wols, F., Kloosterman, J.-L., Lathouwers, D., et al. (2015). Analysis of the running-in phase of a passively safe thorium breeder pebble bed reactor. Annals of Nuclear Energy, 81:227–239.