Operations of decontamination and dismantling generate highly diverse waste in terms of chemical composition and physical form. It can take the form of solid deposits, powders, sludges or liquid solutions. To condition them, encapsulation with a glassy binder seems promising because of its lower working temperature than conventional vitrification processes.
The process involves heating mixtures of waste and vitreous adjuvant between 800 and 1200°C, which requires a deep understanding of the rheological behavior of the system at temperature. Three research directions will be explored during the thesis: the influence of waste loading and nature of the adjuvant on the flow behavior, the behavior of volatile species in mixtures made of wet waste and adjuvant, and the impact of potential reactivity between the waste and the adjuvant on the system properties.
Final objective will be, on one hand, to optimize the container filling rate while maximizing the waste loading rate, on the other hand, to guide the choice of the most suitable vitreous adjuvant.

The PhD student will benefit from the recognized skills of the host laboratory in the field of rheology of complex systems from low temperature (slurries, bitumens, cements) to high temperature (homogeneous and crystallized glass melts), and from all the characterization resources required for the successful completion of the thesis. The entire thesis will be carried out in a non-nuclear environment, using inactive simulants.