Study of the processes related to the water uptake of Eurobitum bituminized radioactive waste: Effect of salt concentration

Research outputpeer-review

Abstract

A coupled hydro-chemical-mechanical constitutive law for the Belgian Eurobitum bituminized waste is being developed by the International Centre for Numerical Methods and Engineering (Polytechnical University of Cataluña, Spain) to contribute to the study of the compatibility of Eurobitum with Boom Clay. A large experimental programme is ongoing at SCK•CEN to support the development of a constitutive law for Eurobitum. Water uptake tests are being performed under different conditions to obtain insights in the parameters that influence the water uptake behaviour of Eurobitum. Furthermore, Environmental Scanning Electron Microscopy and microfocus X-ray Computer Tomography are used to characterize hydrated samples in order to improve the understanding of the water uptake processes. The salt content, the distribution of the salt crystals, and the membrane efficiency in the Eurobitum samples affect the swelling and pressure increase rate. High membrane efficiencies and a considerable amount of hygroscopic salts inside the Eurobitum samples result in very high pressures when almost no swelling is allowed. The pressure in small inactive samples with 28 weight% NaNO3 has risen to ~19MPa after ~3years of hydration in nearly constant volume conditions. Slower pressure increase rates are being measured for samples with 6, 12, 18, and 33 weight% NaNO3.
Original languageEnglish
Title of host publicationScientific Basis for Nuclear Waste Management XXXIII
Subtitle of host publicationSymposium Proceedings
Place of PublicationWarrendale, PA, United States
PublisherMRS - Materials Research Society
Pages513-520
Number of pages8
Volume1193
ISBN (Print)978-1-60511-166-7
DOIs
StatePublished - Dec 2009
Event33rd International Symposium "Scientific Basis for Nuclear Waste Management". MRS - V.G. Khlopin Radium Institute, St. Petersburg
Duration: 24 May 200929 May 2009

Publication series

NameMaterials Research Society proceedings
NumberVolume 1193

Conference

Conference33rd International Symposium "Scientific Basis for Nuclear Waste Management". MRS
Country/TerritoryRussian Federation
CitySt. Petersburg
Period2009-05-242009-05-29

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