16 October 2024

With the official launch of the RCPoroGips-WandPutz research project, the WIR! alliance "Gypsum recycling as an opportunity for the southern Harz region" is continuing its work. The aim of the project is to develop sustainable building products from aerated concrete crushed sand and gypsum. This innovative combination is intended to minimise the use of primary gypsum in the construction industry and make sensible use of aerated concrete waste.

To date, the majority of gypsum used in the construction industry has come from flue gas desulphurisation plants (FGD gypsum), a by-product of fossil energy production. However, with the energy transition and the phasing out of fossil fuels, this source will be severely restricted in future. Without alternatives, the extraction of natural gypsum would have to be increased. To prevent this, the WIR! alliance aims to develop a holistic recycling concept for material flows containing calcium sulphate.

The joint project RCPoroGipsWandPutz aims to develop innovative building products consisting of aerated concrete crushed sand and gypsum. The focus will be on two specific applications: a wall infill supported by a steel frame and a lightweight gypsum plaster. Both products are based on gypsum-bound aerated concrete crushed sand. The project aims to reduce the proportion of gypsum to a minimum while maximising the proportion of aerated concrete crushed sand. This not only helps to conserve primary raw materials, but also gives the demolition material a new, value-adding use.

The technical challenge here lies in adapting the preparation of the aerated concrete rubble to the specific requirements of the building products and achieving suitable fresh mortar properties. While a soft consistency is required for the wall infill, the lightweight plaster must be plastic, adhesive and workable over a sufficiently long period of time.

On 20 August 2024, a project meeting was held at the Thuringian Innovation Centre for Recyclable Materials (ThIWert) in Nordhausen. In addition to the two main project partners - Nordhausen University of Applied Sciences and the Leibniz Institute for Materials-Oriented Technologies (IWT) - the associated partner TodaySystems GmbH from Viersen and the subcontractor BAC Entsorgungswirtschaft GmbH from Bad Tennstedt were also present. Progress to date was presented in a productive atmosphere and further work steps were agreed. The event was rounded off with a tour of the ThIWert laboratories and facilities.

The launch of the RCPoroGipsWandPutz project marks a milestone on the road to a sustainable construction industry. The close cooperation between research institutions, industry and regional players will not only make the Südharz region a model region for sustainable gypsum recycling, but will also help to conserve valuable natural gypsum deposits.the project is funded by the Federal Ministry of Education and Research (BMBF) as part of the "WIR! - Change through innovation in the region" programme.

Funded by the Federal Ministry of Education and Research (BMBF) via the "WIR! - Wandel durch Innovation in der Region" programme.