Sediments Eco-recycling Exploitation, Development and Sustainability

Principal investigator: Elena Landi

Starting date: 28/09/2023
Duration: 24 month
CNR-ISSMC role: Participant
Coordinator: Giovanni Valdrè (Università di Bologna)
Consortium: Università degli Studi di Bologna; Consiglio Nazionale delle Ricerche (CNR-ISSMC); Università degli Studi di Modena e Reggio Emilia; Università degli Studi di Pisa; Università degli Studi di Genova

The main target of SEEDS is to recover selected industrial sediments currently classified and treated as waste and re-use them into the production cycle of construction materials for building and infrastructure (Figure 1). More in detail, the idea is to use waste sediments as “reagents” in partial replacement of virgin raw materials to produce geopolymers and alkali-activated materials (AAMs), improving the eco-sustainability of the building materials production chain, but without compromising (indeed possibly increasing) the performance of the final products. Furthermore, the project will be integrated with parallel toxicity and carcinogenic studies, by effect-directed analysis (EDA) approach. The project is also in line with the objectives of the Italian “Piano Nazionale di Ripresa e Resilienza (PNRR)”, in particular with the missions “Green revolution and ecological transition” and “Infrastructures for a sustainable mobility”.

To this aim, a multidisciplinary method is proposed encompassing mineralogical, materials science, engineering and toxicological knowledge to gain eco-sustainable building materials with suitable characteristics for each specific application. Firstly, mineralogical knowledge on the selected sediments is necessary to develop suitable mixtures to produce the target materials; after, as these materials must satisfy the mechanical properties disciplined by specific standards, engineering knowledge is required. In fact, the use of sediments in the geopolymer matrix undoubtedly will lead to the modification of some properties of the consolidated material (e.g., strength, durability, etc.); nevertheless, these modifications could be linked to the mineralogical composition, which in turn can be properly modulated in mixture design.

To further improve the technological properties of the produced geopolymer/sediment composites, the possibility to include some fractions of other recovered materials (e.g., glass cullet and other inert materials from thermal treatments) could be considered. Some examples are already known for the industrial production of ceramics and could be extended to geopolymers as well.

It should also be stressed that the produced materials will be carefully characterized considering not only their chemical and physical properties, but also their safeness to assess the absence of risks for both human health and the environment, a step which is mandatory to plan the technology transfer.

The SEEDS project aims at obtaining a laboratory validation of the sediments-based products (Technology readiness level, TRL, of 4), with possible extension to preliminary industrial evaluations (TRL 5). Thus, SEEDS is not a mere methodological approach to a looming problem, but it is a new way of rethinking our waste.