A programme of synthesis of a range of model (lab-scale) thermally treated simulant waste materials will be initiated with the addition of active (e.g. U, Th) or inactive (e.g. Cs, Ce for Pu etc.) radionuclide surrogates. We will liaise with NNL to also obtain products of full-scale Geomelt trials (active or inactive) for appropriate waste streams. A suite of characterisation techniques will be applied to understand the thermal, mechanical and chemical properties of the materials, for example, as a function of additives and redox conditions. A particular focus of the work will be to determine the partitioning and local chemical environment of “radionuclide” species within the wasteform materials. Additionally, a series of long term (2.5 year) durability tests will be initiated on selected samples, to understand the influence of key parameters on the durability of the thermal treatment waste products. Finally, a study of the response of selected thermal treatment waste form materials to irradiation will be performed, to assess the effect of dose and dose rate on their mechanical and chemical behaviour.
Academic Lead: Claire Corkhill
Researcher: Daniel Parkes
Location: University of Sheffield