"For innovations to emerge, different people and institutions have to work together: The best example of this is the rECOmine project ZauBer, in which partners from science and industry work together to extract "materials of the future from mining slurries", explains project employee Katja Schaldach. Recently, the project has found its way into society: Pupils from the "Maria Montessori" high school in Freiberg have artistically designed the test containers intended for processing the sludge. The aim was not only to beautify the containers, but also to depict the background and the concerns of the ZauBer project for a wider audience. This sub-project was supported by the new innovation network 4transfer, which is dedicated to the intensive networking of science, business, administration and society in order to strengthen the culture of innovation in Saxony and the region.

ZauBer: Cleaning the "Roter Graben"

In the ZauBer (WIR! - rECOmine) project at the TU Bergakademie Freiberg, technologies are to be developed and tested to clean the Red Ditch. The area contains mining waste water with 17,000 to 18,000 tonnes of unused mine sludge, which is filled with toxic heavy metals such as arsenic, cadmium and lead and endangers nature and animals in the surrounding area. The sludge also contains valuable materials such as aluminium, iron and zinc. The aim of the project is to recycle these. The toxins contained are removed by the project's filter systems. So that this "waste" does not have to be disposed of expensively, the project leaders thought about how to reuse it and came up with an idea.

The company Befesa Zinc Freiberg GmbH has slag left over at the end of its zinc processing. The sludge residue is mixed with the slag from Befesa Zinc Freiberg. This mixture is then used to produce "bricks", which are similar to building bricks. Since the bricks are not suitable for building houses because of the heavy metals they contain, they are to be installed underground in the old Freiberg tunnels to prevent them from collapsing. This will save the city of Freiberg several thousand euros, because otherwise it would have to pump concrete into the Freiberg tunnels. The problem with heavy metals in rivers exists in many old mining regions. Freiberg is one of the first places where this recycling is being carried out. If the project in Freiberg is successful, the plan is that it will also be carried out in other old mining regions.

The processing of the sludge takes place in containers with a pilot plan, which are now also intended to draw the attention of the local population to the project.

Through street art to education

To make this project accessible to the public, the TU Bergakademie Freiberg is cooperating with FGS "Maria Montessori" Freiberg. The task of the Street Art and Smart Mediation student groups, consisting of 16 students, was to spray-paint two overseas containers. The pupils had 5 days to do this. The scientists explained to the pupils how the process works technically and how important the project is for environmental protection. The Street Art group painted the containers with mythical creatures that fit the theme, such as a mud monster and several crystal creatures. The task of the Smart Mediation group was to document the work of the Street Art group and publish the results.