re_pNEU

In recent years, intensive remining concepts have been developed at the Freiberg site, in particular with the participation of UVR and Helmholtz Institute Freiberg for Resource Technology (HIF), with the focus on valuable metal recovery without addressing recovery strategies for the mineral-silicate bulk materials. Flotationally, ways were found to make this possible in principle from representative domestic tin stockpiles. The EU FineFuture project, which ran until the end of November 2022 and involved Technical University Dresden (TUD) and HIF, has also yielded innovations and efficiency improvements in the field of pneumatic fine particle flotation, specifically in the turbulence design of the reactor section. Furthermore, the building materials experts of Technical University Chemnitz (TUC) and LIM described the potentials of the residual materials in the Saxon tin tailings of Ehrenfriedersdorf and Altenberg-Tiefenbachhalde for the use of building materials.

On this profound basis, the technical project re_pNEU "Remining by fine particle processing of tin dumps in the Ore Mountains with innovative pNEUmatic flotation technology, more sustainable processing strategies and recycling potential of silicate residues in stones and cobbles" combines several technology innovations, which can also be used individually, to form a joint project with potential cross-regional impact.

The project aims at the remining of tin heaps from the Ore Mountains by the processing of fine particles with the core of the innovative pNEUmatic flotation, equipped with new sensor concepts towards a digitalized separation technology. The use of sustainable flotation reagents and the preparation of the mineral-silicate residues for use and the development of formulations for ecological paving stones as building materials are further project goals. Thus, re_pNEU will lead to the strengthening of the region through the following project objectives:

• Technological improvement and technical-scientific deepening of fine particle flotation at HIF and, in addition, the associated establishment of an internationally active equipment developer (Maelgwyn Mineral Services) in Freiberg,
• Sensor system development in Dresden (TUD and HZDR Innovation) for use in the globally economically significant flotation process for process digitization,
• Competence expansion and strengthening of Freiberg processing in basic engineering and process development at UVR for projects of remining and tailings recycling with focus on tailoring for the use of the residues in building materials, and
• Expansion of processing technologies and building materials technology engineering formulation for the production of sustainable paving stones using indigenous silicate-mineral residues at TUC and LIM.