Influence of high nitrate salts concentration on dimensional variations of mortars under wet curing - Archive ouverte HAL Accéder directement au contenu
Communication Dans Un Congrès Année : 2008

Influence of high nitrate salts concentration on dimensional variations of mortars under wet curing

Résumé

Cementation is a widely applied technique for the conditioning of low- and intermediate-level radioactive wastes. In particular, the use of cement is an attractive procedure to immobilize evaporator concentrates from aqueous effluents treatment. This study is devoted to bring information on the influence of concentrates mixing solution on the dimensional variations under wet curing of simulated solidified waste forms with high ionic strength. In this study, the salinity of the evaporator concentrates was simulated by adding sodium or potassium nitrates. The length changes were measured, with displacement gauges consisting in linear variable differential transducers. Mortars prepared with solutions of KNO3 or NaNO3 exhibited expansion which increased with the nitrate concentration in the mixing solution, whatever the associated cations. The measured swelling was shown to be governed by a concentration effect which involved diffusion and osmosis: diffusion of the ions of the pore solution into the less concentrated curing solution, and water uptake by the material due to the osmotic pressure gradient between the pore and curing solutions.

Domaines

Matériaux
Fichier non déposé

Dates et versions

hal-00452394 , version 1 (02-02-2010)

Identifiants

  • HAL Id : hal-00452394 , version 1

Citer

Philippe Benard, Sandrine Garrault, C. Cau Dit Coumes, André Nonat. Influence of high nitrate salts concentration on dimensional variations of mortars under wet curing. Workshop on waste cement hydration, 2008, Nantes, France. ⟨hal-00452394⟩
29 Consultations
0 Téléchargements

Partager

Gmail Facebook X LinkedIn More