Ash-Derived Paving Stones
Ghent Researchers Develop Sustainable Paving Stones from Leftover Ash
Kanesa D — October 10, 2025
Ghent University researchers have developed paving stones made from household waste ash. The project is part of the AshCycle pilot, a Horizon Europe initiative that transforms incineration ash into sustainable building materials.
The collaboration includes Veolia, Ghent University, ResourceFull, Orbix, and SECO, with Professor Stijn Matthys leading the charge on Ghent's end. Ash from waste plants is processed in Grimbergen and then tested in Ghent, where scientists assess its strength, durability, and environmental footprint. Two 50-square-meter test zones have been installed on campus—one made with alkali-activated materials and the other with Carbstone technology, which captures CO₂ during production.
“This is a CO₂-negative stone”, said Professor Matthys. “We use CO₂ ‚ together with ash and metal slags to form solid concrete. On a European scale, the technology could save up to 20 megatonnes of CO₂ annually. It’s not a miracle solution, but it’s a meaningful step towards a greener construction industry.”
