This research aimed to investigate the potential of using alkali activation technology to valorize steel slag and bauxite residue for the production of high-performance pavement blocks. By utilizing these industrial by-products, the study seeks to reduce their environmental impact and support the development of sustainable construction materials. Lab-scale testing showed that bauxite pavers showed a decrease in mechanical strength with increasing replacement of ordinary Portland cement. Partial replacement up to 20% still exceeded 30 MPa in compressive strength. Steel slag-based pavers achieved the 30 MPa threshold required for the application with selected mix designs. Pilot-scale production-optimized formulations and standards testing, including freeze–thaw resistance, confirmed the technical viability of these products. Life cycle analysis indicated a 25–27% reduction in CO₂ emissions for slag-based tiles compared to traditional concrete tiles. Moreover, using industrial residue reduced mineral resource depletion. This study examined the properties of the resulting alkali-activated binders, their ecological benefits, and their performance compared to conventional materials. Through a comprehensive analysis of these applications, our research promotes the circular economy and the advancement of sustainable construction products.

Replacing conventional materials with new recycled materials is one of the goals of sustainable development, as it promotes the creation of environmentally friendly products while reducing the amount of waste to be treated. A common recyclable waste stream associated with urban living is waste glass, which typically comes from packaging or product containers. Although most of this stream can be reused and/or recycled, it is worth exploring alternative uses, especially for areas with high fluctuations in waste glass production. An example would be the sudden increase in waste glass in tourist areas during the high season. To this end, the present work presents the results from the life cycle assessment of waste glass geopolymerization for the production of cement tiles. The methodology includes the estimation of mass and energy balances by dividing the whole process into several sub-processes (NaOH addition, energy consumption, etc.). The NaOH addition was found to be the most burden-intensive process, with a total damage of 9 × 10⁻⁵ DALY per ton of waste glass in the human health category, while a minor contribution in all damage categories was attributed to process electricity demands (7.7 to 19.4%). By comparing the geopolymerization process with conventional recycling, an environmental benefit of 20 mPt and 26 kg CO₂ per ton of waste glass was demonstrated, indicating the process’s expediency. The present study is a valuable tool for the up-scaling of processes towards a circular economy.

Scandium (Sc) applications in solid oxygen fuel cells, aeronautics and heat exchange systems are forecasted to increase significantly without a sufficient continuous Sc supply for Europe. ScaVanger is an EU project for upscaling Sc extraction and purification technologies from various TiO₂ pigment production residues. High purity Sc₂O₃ and ScF₃ will be produced at competitive prices for the EU market. The ScaVanger process is expected to result in a 10% higher production rate and higher product purity as processing starts with a unique cleaning process of actinides. The first plant at a major European TiO₂ pigment production site will be supplying about 30 t/a of Sc₂O₃.

Technology of alkali activation is an alternative sustainable approach to producing paving paver, where reactive aluminosilicate precursor undergoes a reaction with an alkaline solution to form binded product. The case study presents the functional usability of a technology as part of the Georis project. The construction pavers are composed of over 75% industrial residues, with the majority of the materials sourced from steel slag industry. Laboratory testing of pavers confirmed the promising mechanical properties, demonstrating high compressive and flexural strength, as well as resistance to frost and abrasion. The results support the feasibility of scaling up from lab-scale to pilot manufacturing. The innovative approach in this project was the pilot production process itself, where more than 20 m² of pavers were manufactured and cured in a mobile unit. To assess their real-world performance, a demonstration case was implemented at the SIJ Acroni courtyard, where the pavers were installed to observe their application in a practical setting and to monitor their long-term durability. The valorisation of residues within GEORIS pavers highlights lower CO₂ emissions compared to conventional cement-based pavers and the potential of technology for industrial symbiosis and circular economy initiatives, making it an attractive solution for environmentally conscious industries.