Long-term performance of waste matrices (L'OPERA)
Objectives
Demonstrate long term behaviour and durability of matrices and final wasteforms.
Description of the WP
Matrices such as geopolymers and others such as magnesian cements, are alternatives to immobilize and encapsulate Low and Intermediate Level Waste (LL-ILW). Although some of them have been used in the past, knowledge of these materials is less mature (compared to other conditioning matrices) and the understanding of their long-term performance and durability under disposal conditions is required to consider them for the conditioning of specific wastes and obtain final wasteforms which can meet the WAC of the disposal facilities.
Initiated during previous European projects (e.g. PREDIS) Solid and Liquid Organic Waste as well as the decontamination effluents were immobilised using different processes. However, the long-term performance of the resulting materials still has to be evaluated. Thus, WP7 aims to complete this evaluation, allowing an increase of the TRL of the selected processes, but also to evaluate the long-term behaviour of other promising final wasteforms coming from innovative processes and to define the most suitable routes for the long-term management of LL-ILW.
Some of these matrices, such as geopolymers and polymer matrices, have shown good properties for the waste encapsulation and short-term performances, but their long-term behaviour under disposal conditions is quite unknown. The understanding of the degradation behaviour and its consequences on the performance of the wasteforms is required, as well as extrapolation to a few hundred years for surface disposal and to longer periods for geological disposal.
Outcomes
- Better understanding of long-term behaviour of waste matrices/wasteforms in disposal conditions (near surface disposal and deep geological disposal)
- Identifying degradation processes and their elemental drivers
- Diffusion and leaching values of new matrices/wasteforms
- Disposability assessment and demonstration according to disposal facilities features (near-surface and/or intermediate-depth and/or geological)
