Medium-active waste form characterization : The performance of cement-based systems
The properties of cement systems which contribute to their immobilisation potential for radwastes are characterised. In the short term, both physical and chemical properties of the matrix contribute to the immobilisation potential, but in the longer term, chemical effects dominate. Before the interactions of cement with wastes can be fully assessed and data extrapolated into the future, it is necessary to be able to describe quantitatively the behaviour of cements themselves. A rigorous framework based on accessible physico-chemical variables has been constructed. The model, as presently developed, is capable of describing the future performance of cements when leached at approx. 20 C by relatively pure water. It covers primarily six chemical components - Na(2)O, K(2)O, CaO, MgO, SiO(2) and water - together with limited data on the effect of sulphate. The interaction of cements with inactive waste-stream constituents, principally sulphate and nitrate, is described. The interaction between steel and cement is also re-examined. As a consequence of these studies, a firm scientific basis has been laid for modelling the behaviour of cemented systems over long periods, which extend beyond those for which test data can be obtained.
Bibliographic Reference: EUR 13542 EN (1991) 164 pp., FS, ECU 13.75
ISBN: ISBN 92-826-2908-2
Record Number: 199111303 / Last updated on: 1994-12-02
Original language: en
Available languages: en