The evolution of the cement industry towards reducing its environmental footprint is expected to lead to the gradual disappearance of high-clinker binders, which are currently used for the conditioning of certain types of radioactive waste, such as evaporator concentrates. In contrast, novel cements (e.g., CEM II/C-M, CEM VI, LC3) are under development or standardization, offering new opportunities to design cement-based matrices with reduced environmental impact. However, their performance needs to be thoroughly evaluated to anticipate their industrial implementation for radioactive waste management.
This project will focus particularly on the influence of key ionic species present in evaporator concentrates on the hydration of ternary binders consisting of clinker, calcined clay, and limestone filler. Experiments will be conducted using non-radioactive surrogates. In addition to commercial cements, laboratory-prepared mixes will be used, allowing for more precise control over the content of clinker and supplementary cementitious materials. To understand the mechanisms involved in ion-induced acceleration or retardation of cement hydration, the hydration rate, phase evolution and microstructure will be investigated using a variety of techniques. The experimental results will then be used as input data for thermodynamic modelling of the hydration of these low-carbon binders by concentrated electrolytes.
This project is aimed at a postdoctoral researcher interested in developing expertise in materials chemistry and thermodynamic modeling, with a focus on advancing low-carbon cement chemistry and exploring new solutions for radioactive waste conditioning. It will be conducted within the framework of the EURAD2 European project at the Design and Characterization of Mineral Materials Laboratory (CEA/LFCM), with opportunities for collaboration with other European laboratories.