The osmosis-induced swelling and NaNO3 leaching of radioactive and artificially aged Eurobitum bituminized waste

Research outputpeer-review

2 Scopus citations

Abstract

The behavior of Eurobitum bituminized radioactive waste under geological disposal conditions is studied in water uptake tests at the Belgian Nuclear Research Centre SCK•CEN to assess the feasibility of geological disposal for the long-term management of this waste. The hydro-mechanical behavior of this waste is affected by the continuous evolution of the rheological properties of bitumen due to radio-oxidation (i.e. ageing). The effect of the bitumen ageing degree on the kinetics of the water uptake, swelling and NaNO3 leaching is investigated in water uptake tests with ∼30 years old radioactive samples and inactive samples that were artificially aged. The first results of swelling and NaNO3 leaching of (i) radioactive samples that have been hydrated for more than 2 years at a constant total stress of 2.2 MPa, and (ii) a thermally aged sample that has been hydrated for ∼1.5 years under nearly zero effective stress conditions, revealed lower swelling and higher leach rates for these samples compared to non-aged samples. The effect of ageing on the osmotic efficiency of bitumen as a semi-permeable membrane is less pronounced when swelling of the samples is limited, and changes in time, probably because of the formation of low porosity layers, which seems to mask the difference in bitumen membrane efficiency of aged and non-aged bituminized waste.

Original languageEnglish
Title of host publicationScientific Basis for Nuclear Waste Management XXXV
PublisherMRS - Materials Research Society
Pages113-118
Number of pages6
Volume1475
ISBN (Print)9781605114521
DOIs
StatePublished - 2012
Event2012 MRS Spring Meeting - San Francisco, CA
Duration: 9 Apr 201213 Apr 2012

Publication series

NameMaterials Research Society Symposium Proceedings
Volume1475
ISSN (Print)0272-9172

Conference

Conference2012 MRS Spring Meeting
Country/TerritoryUnited States
CitySan Francisco, CA
Period2012-04-092012-04-13

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

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