Understanding acid consumption and its relationship with copper recovery

Acid consumption in copper heap leaching is significantly influenced by the minerals present in the ore, including both gangue minerals like biotite and chlorite, and copper-bearing minerals such as chrysocolla and malachite. This study aims to elucidate the relationship between acid consumption and copper recovery by analyzing various factors such as the rate of acid application, particle size, and mineral alterations during the leaching process. Detailed measurements were conducted to assess the acid consumption of specific gangue minerals, alongside the resulting copper recovery from a particular copper ore sample. The findings reveal that higher acid consumption is related to specific mineralogical compositions and demonstrate a clear correlation between solution pH and copper recovery levels. Furthermore, various techniques for quantifying acid consumption in minerals and mineral blends were also examined. This comprehensive analysis provides valuable insight into the relationship between pH, acid consumption, and copper recovery during sulfuric acid leaching of copper from oxide ore, highlighting the technical challenges posed by ores with high acid consumption.