Chemical durability of high-level waste glass in repository environment: main conclusions and remaining uncertainties fr
- PDF / 272,601 Bytes
- 12 Pages / 612 x 792 pts (letter) Page_size
- 111 Downloads / 230 Views
Chemical durability of high-level waste glass in repository environment: main conclusions and remaining uncertainties from the GLASTAB and GLAMOR projects P. Van Iseghem1, K. Lemmens1, M. Aertsens1, S. Gin2, I. Ribet2, B. Grambow3, J.L.Crovisier4, M. Del Nero5, E. Curti6, B. Schwyn7, B. Luckscheiter8, T. McMenamin9 1 SCK•CEN, Mol (Belgium) 2 CEA-Valrhô, Marcoule (France) 3 Subatech, Nantes (France) 4 EOST Centre de Géochimie de la Surface, Strasbourg (France) 5 IreS, Strasbourg (France) 6 PSI, Villigen (Switzerland) 7 NAGRA, Wettingen (Swizerland) 8 FZK,Karlruhe (Germany) 9 European Commission, Brussels (Belgium) ABSTRACT This paper reviews the main conclusions of two European Commission funded projects, GLASTAB and GLAMOR, on the durability of HLW glass in geological disposal, and the remaining uncertainties. The progress in GLASTAB relates to the characterization of the alteration layer, the modeling of glass dissolution, the interaction of glass with near field materials, the behaviour of radionuclides, and the calculation of HLW glass dissolution as part of geological disposal. The GLAMOR programme was focused on the decrease of the glass dissolution rate upon achieving silica saturation in solution. Two conclusions from this programme are the importance of the residual rate measured beyond silica saturation and the need to reduce the uncertainties in model parameters. The overall conclusion from the two projects is that strong progress has been achieved on basic dissolution mechanisms and interaction with disposal environments - HLW glass will act as a good barrier to the release of radionuclides in geologic disposal.
INTRODUCTION The durability of vitrified high-level waste in contact with water has been investigated for more than 30 years [1-6]. Generally speaking, the research has shifted from initially qualification tests of candidate HLW glasses over long-term leaching tests in different solutions to durability tests and associated modeling in disposal media. This evolution occurred in parallel with the selection of a few glass compositions for industrial use, the selection of candidate geological disposal sites, and the elaboration of performance assessment studies for these sites. Another evolution in the European Commission (EC) projects was the increasing integration of the research at the different European Union (EU) participating laboratories into the same project. This paper presents a critical review of the state-of-the-art of the chemical durability of HLW glass in repository environment, based on the output of two projects carried out within the framework of the past 5th EC framework programme : GLASTAB and GLAMOR [7, 8]. The GLASTAB programme was an integrated effort, closely related to a previous project [9], and focused on improving the database for glass dissolution, the understanding of the alteration
Downloaded from https://www.cambridge.org/core. Access paid by the UCSB Libraries, on 21 Mar 2018 at 10:23:40, subject to the Cambridge Core terms of use, available at https://www.cambridge.
Data Loading...
