Biometallurgy is a branch of extractive metallurgy that describes biotechnological processes that involve interactions between microorganisms and metal-bearing minerals to recover metals from mineral ores, concentrates, and a range of waste materials. Bioleaching and bioremediation are two of the most studied branches in this field and are employed worldwide at commercial scale.
Mintek has established an internationally recognised position for the treatment of sulphide ores and concentrates bearing gold and base metals. The tank bioleaching technologies developed by Mintek have been commercialised and typically find application in niche areas for the treatment of refractory gold concentrates, as well as complex polymetallic concentrates that contain impurities that attract smelting penalties.
With the depletion of higher-grade resources, technology development has diversified to include heap leach applications where metals are extracted from minerals contained in dumps or stacked heaps of low grade ores. The learnings from biological heap leaching have been expanded to include acid, alkaline and chloride heap leaching in the division’s portfolio. In addition, Mintek has the unique ability to combine percolation leach test work with the geomechanical (hydraulic/hydrodynamic) testing of such ores and their leach residues.
There is a global trend to move the mining industry towards participating in a circular economy by promoting and investing in sustainable solutions and green technologies. Mintek is uniquely positioned to contribute to this drive through its multidisciplinary capabilities, which include bioprocessing and chemical and environmental engineering. The development and implementation of technologies for treatment of mine impacted water to produce water that is fit for re-use in activities such as community use and irrigated agriculture forms part of this portfolio.