Austrian Laboratory develops waste-based geopolymer construction to build materials from residual and waste products

Portland-cement-based concrete, the most common type of concrete used in construction, may be partially replaced in the near future via emerging sustainable concrete mixtures that are created from mineral residues and waste materials.

This is what a project from the new Christian Doppler Laboratory of the Institute of Applied Geosciences at Graz University of Technology in Austria aims to achieve in their waste-based geopolymer construction. The novel approach may play key roles in application environments prone to corrosion such as sewage systems, biowaste plants, or tunnel drainage systems.

The project’s potential in using rubble, slag, metallurgical gravel, mineral wool, or ash, is seen as a more environmentally friendly and resistant concrete alternative.

The project is headed by Cyrill Grengg, partnered with 8 important corporate partners, including the Austrian Research Association of the Stone and Ceramic Industry and the Community of Styrian Wastewater Disposal Companies. Its largest public funding body includes the Austrian Federal Ministry of Labour and Economic Affairs (BMAW).

Production of waste-based waste-based geopolymer

The Christian Doppler Laboratory facilitates waste-based geopolymer construction by using inorganic industrial secondary raw materials like slag and ash, as well as residual materials, like mineral wool and clay-rich demolition materials. Such is combined with carbon-rich waste material like waste oils, biomass residues, or organic fibers which varies based on demand and intended use.

The resulting polymer is found to be more resistant to corrosion compared to conventional Portland cement-based concrete. “Chemically, the geopolymer is something completely different from Portland cement, but the physical properties are very similar or even better in some cases,” says Grengg.

In Austria, they generate whopping 54 million tonnes of mineral waste annually, 76 percent of which comes from total waste volume. Of this, almost 60% goes to landfill, resulting in valuable loss of resources and areas of land due to the landfill. Grengg and his team see this as an opportunity to recover economic loss and contribute to environmental conservation by means of waste-based geopolymers.

“We want to take these materials away from landfills and integrate them into a CO2-neutral recycling economy.”

Currently, the Christian Doppler laboratories carry out application-oriented research and best-practice approach in wast-based geopolymers to further innovations in concrete production.