Alternative circular binder made from ettringite

Several Walloon companies, including in particular Sedisol, SWDE and IPALLE, are faced with difficulties when it comes to the management of their waste. Yet, it turns out that the pooling of certain of these wastes leads to the formation of a particular hydraulic phase which could serve as a binder in the context of the synthesis of materials with limited lift, such as self-compacting materials which can be re-excavated (SMR), or subbase materials. As far as the SMR are more specifically concerned, these materials have high developmental potential because whilst they meet a real need, they are little used in the Walloon Region. Moreover, the synthesised phase enables the inorganic pollutants present in the waste to be stabilised and a large number of water molecules to be captured, in this way contributing to the stiffening of the materials.

The aim of this project is thus to develop these eco-materials whose lift is provided by this particular phase. The original character is further reinforced by the fact that the reactants enabling this phase to be synthesised are all of secondary origin, which means their being disposed of in an engineered landfill site can be avoided.

The CTP will intervene in this project in the characterisation of secondary mineral materials, as well as in the phase involving the development of eco-materials made from these materials and including the particular hydraulic phase. The eco-materials will serve as the basis of the formulation of SMR and subbase materials by another partner.