The “Re-mining” project focuses on the overburden of former mining tailings. The aim is to recover the important metals and minerals they contain, such as indium, zinc and copper. In addition, the remaining overburden would then be free of pollutants such as arsenic and cadmium, and would remain as a spoil tip without further contaminating the environment. For this “Re-mining”, the project team is using advanced bioleaching, which was developed in a previous project, and which is able to recover up to 90 percent of the reusable materials.
The new process is applied on site in an industrial demonstration plant in Freiberg. This plant is to demonstrate the functionality in industrial practice to potential national and international clients. It consists of three modules and is designed to be semi-mobile – it can be transported to other spoil tips and installed there at low cost.
During a one-year project planning phase, all the legal permit issues are resolved, the plant is planned and special equipment constructed. The subsequent two-year project phase covers construction, commissioning and optimization of the plant as well as the development of a marketing strategy and business plan. After completion of the project, the technology will be marketed internationally.
As the geotechnical engineering service provider and process developer of the bioleaching technology, the engineering firm G.E.O.S. Ingenieurgesellschaft is responsible for project management and, together with the Helmholtz Institute Freiberg for Resource Technology, for planning, constructing and analyzing the plant as well as the marketing strategy. Saxonia Standortentwicklungs- und -verwaltungsgesellschaft mbH sorts out all the site issues and is responsible for managing the required permits.