Modelling experimental results on radiolytic processes at the spent fuel water interface. I. Radiolysis products and U release
2004 (English)In: SCIENTIFIC BASIS FOR NUCLEAR WASTE MANAGEMENT XXVII, 2004, 397-402 p.Conference paper (Refereed)
Experimental and modelling efforts in the last decade in the frame of nuclear waste management field have been focused on studying the role of the UO2 surfaces in poising the redox state of solid/water systems. For this purpose, an experimental programme was developed consisting on dissolution experiments with PWR spent fuel fragments in an anoxic environment and by using different solution compositions. The collected data so far, indicate that production and fate of radiolysis products follow the same trends independently on the solution composition used in the tests. Hydrogen and oxygen concentrations show an initial increase with time until reaching a constant concentration. The trend observed for hydrogen peroxide is a decrease at short contact times to reach again a constant concentration with time. These steady-states indicate an overall balance of the generated radiolytic species. Modelling work indicates that uranium dissolution is controlled by the oxidation of the spent fuel matrix in 10mM bicarbonate solutions while in the tests carried out at lower or without carbonate concentrations uranium in the aqueous phase is governed by the precipitation of schoepite. These results are determinant to highlight that reducing conditions are restored in the aqueous phase in relatively short periods of time and at short distances away from the dynamic redox spent fuel/water interface.
Place, publisher, year, edition, pages
2004. 397-402 p.
, Materials Research Society Symposium Proceedings, ISSN 0272-9172 ; 807
Contacts (fluid mechanics), Dissolution, Hydrogen peroxide, Nuclear fuel elements, Oxidation, Radioactive wastes, Radiolysis, Redox reactions, Uranium dioxide, Bicarbonate, Nuclear waste management, Oxidants, Spent fuel fragments, Spent fuels
IdentifiersURN: urn:nbn:se:kth:diva-157732ISI: 000225038400065ScopusID: 2-s2.0-12944260463ISBN: 1-55899-752-0OAI: oai:DiVA.org:kth-157732DiVA: diva2:771660
Scientific Basis for Nuclear Waste Management XXVII, 15 June 2003 through 19 June 2003, Kalmar, Sweden
QC 201412152014-12-152014-12-122014-12-15Bibliographically approved