Accumulated sludge in (formerly) mine water facilities is a major environmental problem and usually only treated as hazardous waste even though the sludge contains economic relevant elements. Within the project a field test laboratory at the “Roter Graben” - a mining canal heavily clogged with ferruginous sludge, at Freiberg  - is built up. The pilot-scale system, combines a multi-stage membrane system with a chamber filter press and precipitation line for the continuous treatment of mining waters and the batch recycling of the sludge in the scale of tons to a starting stock for geopolymer building materials. 

In recent weeks, all system components, which are divided into 2 containers, have been connected to each other and the process control system has been completed. All by the authority’s required safety precautions have also been arranged. Until the final approval is granted, the system is now undergoing comprehensive testing operations.

The project is a cooperation between the Institute of Thermal, Environmental and Resources’ Process Engineering (ITUN), the Institute of Technical Chemistry, Terra Mineralia, SAXONIA Standortentwicklungs- und Verwaltungsgesellschaft mbH, INTEC Gesellschaft für Injektionstechnik mbH & Co. KG, Befesa Zinc Freiberg GmbH and G.E.O.S. Ingenieurgesellschaft mbH, funded by BMBF in the framework of rECOmine.