TY - JOUR
T1 - Effect of hydrogen gas and leaching solution on the fast release of fission products from two PWR fuels
AU - Mennecart, Thierry
AU - Iglesias Pérez, Luis
AU - Herm, Michel
AU - König, T.
AU - Leinders, Gregory
AU - Cachoir, Christelle
AU - Lemmens, Karel
AU - Verwerft, Marc
AU - Metz, Volker
AU - González-Robles, Ernesto
AU - Meert, Katrien
AU - Vandoorne, Tomas
AU - Gaggiano, Roberto
N1 - Score=10
Funding Information:
This work was performed as part of the program of the Belgian Agency for Radioactive Waste and Enriched Fissile Materials (NIRAS/ONDRAF) on the geological disposal of high level/long-lived radioactive waste. The authors gratefully acknowledge the technical support from J. Pakarinen, G. Cornelis, B. Gielen, P. Schroeders and G. Cools at SCK CEN, and C. Beiser, E. Bohnert, M. Böttle, M. Fuss, F. Geyer, N. Müller and A. Walschburger at KIT-INE, as well as the workshop staff of both institutes. The SCK CEN group thank also AREVA, Electrabel and Tractebel for the data related to the Belgian fuel rod. The authors would like to thank X. Gaona for providing valuable information on the thermodynamics of actinides and fission products.
Publisher Copyright:
© 2023 The Author(s)
PY - 2024/1/1
Y1 - 2024/1/1
N2 - To study the dissolution of UOX spent nuclear fuel in a deep geological environment and the fast release of a selection of relevant radionuclides for long-term safety of this high level waste, leaching experiments were performed with spent nuclear fuel samples originating from the pressurized water reactors (PWRs) Tihange 1 and Gösgen with a similar burnup (50 – 55 MWd.kg
HM
−1) but different irradiation histories. Six experiments were conducted to investigate the effect of two critical parameters: (1) the highly alkaline environment caused by the presence of cementitious materials in the “Supercontainer design”, which is currently the reference design for the long-term management of the high-level nuclear waste forms in Belgium, and (2) the reducing conditions imposed by the presence of hydrogen from the corrosion of iron-based materials present in the engineered barriers. The experiments were performed using autoclaves under pressure from 1 to 40 bar with a pure Ar atmosphere or a mixture of H
2/Ar. Divided into two consecutive phases, the total experimental duration was about 1400 days. The Phase I provided mainly information about the fast release of the fission products while the perspective of the Phase II was to study the long-term evolution of the spent fuel matrix. During the leaching experiment, concentrations of a selection of radionuclides (
238U,
129I,
137Cs,
90Sr and
99Tc) were monitored in solution and the amounts of Kr and Xe were measured in the gas phase. Based on results of the experiments conducted for up to 40 months (i.e. during Phase I of the experimental program), we observe that there is a continuous release of
137Cs,
90Sr and of the fission gases and a clear impact of the irradiation history on the release of certain fission products.
AB - To study the dissolution of UOX spent nuclear fuel in a deep geological environment and the fast release of a selection of relevant radionuclides for long-term safety of this high level waste, leaching experiments were performed with spent nuclear fuel samples originating from the pressurized water reactors (PWRs) Tihange 1 and Gösgen with a similar burnup (50 – 55 MWd.kg
HM
−1) but different irradiation histories. Six experiments were conducted to investigate the effect of two critical parameters: (1) the highly alkaline environment caused by the presence of cementitious materials in the “Supercontainer design”, which is currently the reference design for the long-term management of the high-level nuclear waste forms in Belgium, and (2) the reducing conditions imposed by the presence of hydrogen from the corrosion of iron-based materials present in the engineered barriers. The experiments were performed using autoclaves under pressure from 1 to 40 bar with a pure Ar atmosphere or a mixture of H
2/Ar. Divided into two consecutive phases, the total experimental duration was about 1400 days. The Phase I provided mainly information about the fast release of the fission products while the perspective of the Phase II was to study the long-term evolution of the spent fuel matrix. During the leaching experiment, concentrations of a selection of radionuclides (
238U,
129I,
137Cs,
90Sr and
99Tc) were monitored in solution and the amounts of Kr and Xe were measured in the gas phase. Based on results of the experiments conducted for up to 40 months (i.e. during Phase I of the experimental program), we observe that there is a continuous release of
137Cs,
90Sr and of the fission gases and a clear impact of the irradiation history on the release of certain fission products.
KW - Spent nuclear fuel
KW - Leaching experiments
KW - Fission products
KW - Fast release
KW - Reducing conditions
KW - H2 effect
KW - High pH conditions
KW - H effect
UR - https://ecm.sckcen.be/OTCS/llisapi.dll/open/81136378
UR - http://www.scopus.com/inward/record.url?scp=85177488369&partnerID=8YFLogxK
U2 - 10.1016/j.jnucmat.2023.154811
DO - 10.1016/j.jnucmat.2023.154811
M3 - Article
SN - 0022-3115
VL - 588
JO - Journal of Nuclear Materials
JF - Journal of Nuclear Materials
M1 - 154811
ER -