A Sustainable Bioleaching of a Low-Grade Chalcopyrite Ore

This paper reports on a study of column bioleaching low-grade chalcopyrite ore that is currently dump-leached under natural biological conditions without any control over microbial populations. The experimental methodology was focused the effect managing bacterial populations in raffinate solution sourced from dump-leach operation. presents results columns two heights (0.45 and 1.0 m). We demonstrated intermittent irrigation enhanced dissolution during leaching, but excessively long rest periods negatively affected chemical activity due to shortage oxidizing agents and/or nutrients for microorganisms. recovery by increasing cell density. addition 1.5 × 108 cells/mL 0.45 m 5.0 107 1 resulted increased extraction, with copper 32% 44% 30% 40% 70 days leaching. Under these conditions, pH level remained constant at ~1.8, redox potential around 840 mV vs. SHE throughout experiment. These provided useful insights evaluating sustainable controlled dump-based technology mineral bioprocessing.