Program - Brookhaven National Laboratory

Accurate and reliable nuclear data and their uncertainties are important in the design, modeling and
development of GEN-IV reactors. As part of GEN-IV research in the Universities in Sweden, the design
and development of a plutonium-fueled European Lead-Cooled Training Reactor (ELECTRA) [1] was
proposed and it is envisaged that it will provide practical experience and experimental data for research
and development of GEN-IV reactors. In this paper, the global effect of Pb-208 and Pu-239 cross section
data uncertainties on the k-eff, Doppler constant, coolant temperature coefficient, void coefficient and the
effective delayed neutron fraction are investigated and analyzed. The analyses were carried out for the
ELECTRA reactor using the Total Monte Carlo method proposed in Ref [2]. A large number of Pb-208
and Pu-239 random ENDF-format libraries, generated using the Talys based system [3] and processed into
ACE format using Njoy99.336, are used as input into the Serpent Monte Carlo code to obtain the reactor
safety parameters. Parameter distributions for the different isotopes are compared with the latest major
nuclear data libraries; JEFF-3.1.2, ENDFB/VII.1 and JENDL-4.0. Finally, based on obtained values of
chi squared from Ref [3], we investigated if an accept/reject criteria can reduce the uncertainty in reactor
parameters.
[1] Wallenius, J., Suvdantsetseg, E., and Fokau, A., 2012. ELECTRA: European Lead-Cooled Training
Reactor. Fission Reactors. Nuclear Technology Vol. 177, p. 303-313. [2] Koning, A.J., and Rochman, D.,
2008. Towards sustainable nuclear energy: Putting nuclear physics to work. Annals of Nuclear Energy 35,
p. 2024-230. [3] Rochman, D., and Koning, A.J., 2011. How to randomly evaluate nuclear data: A new
data adjustment method applied to Pu-239. Nuclear Science and Engineering 168(1), p. 68-80.
HE 8 5:45 PM
Neutronic Study of Burnup, Radiotoxicity, Decay Heat and Basic Safety Parameters of
Mono-reycling of Americium in French PWR
R.B.M. Sogbadji, S. David, E.H.K. Akaho, B.J.B. Nyarko
Ghana Atomic Energy Commission, National Nuclear Research Institute,Nuclear Reactors Research
Center, Kwabenya, Ghana
The MURE code is based on the coupling of a Monte Carlo static code and the calculation of the evolution
of the fuel during irradiation and cooling periods. The MURE code has been used to analyse two different
questions, concerning the mono-recycling of Am in present French Pressurized Water Reactor. The UOX
fuel assembly, as in the open cycle system, was designed to reach a burn-up of 46GWd/T and 68GWd/T.
The spent UOX was reprocessed to fabricate MOX assemblies, by the extraction of Plutonium and addition
of depleted Uranium to reach burn-ups of 46GWd/T and 68GWd/T, taking into account various cooling
times of the spent UOX assembly in the repository. The effect of cooling time on burnup and radiotoxicity
was then ascertained. Spent UOX fuel, after 30 years of cooling in the repository required higher
concentration of Pu to be reprocessed into a MOX fuel due to the decay of Pu-241. Americium, with a
mean half-life of 432 years, has high radiotoxic level, high mid-term residual heat and a precursor for other
long lived isotope. An innovative strategy consists of reprocessing not only the plutonium from the UOX
spent fuel but also the americium isotopes which dominate the radiotoxicity of present waste. The monorecycling
of Am is not a definitive solution because the once-through MOX cycle transmutation of Am in
a PWR is not enough to destroy all the Am. The main objective is to propose a “waiting strategy” for
both Am and Pu in the spent fuel so that they can be made available for further transmutation strategies.
The MOXAm (MOX and Americium isotopes) fuel was fabricated to see the effect of americium in MOX
fuel on the burn-up, neutronic behavior and on radiotoxicity. The MOXAm fuel showed relatively good
indicators both on burnup and on radiotoxicity. A 68GWd/T MOX assembly produced from a reprocessed
spent 46GWd/T UOX assembly showed a decrease in radiotoxicity as compared to the open cycle. All fuel
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