Copper extraction and processing present both technical and environmental challenges, and alkaline reagents like hydrated lime are playing an increasingly central role. Used mainly as a pH regulator, hydrated lime helps shift mining operations towards greater efficiency while also reducing environmental risk.
In the flotation stage of copper processing, maintaining the right pH is crucial. Many flotation reagents are sensitive to acidity; if the slurry becomes too acidic, recovery of copper minerals suffers. Introducing hydrated lime raises pH, which stabilises flotation conditions, improving separation of the valuable copper-bearing minerals from waste.
Tailings management is another area where lime additives are proving useful. Tailings often contain residual acidity and heavy metals. By applying hydrated lime, operators can increase pH, precipitate out or immobilise metals, and thus reduce the mobility of contaminants.
From an operational economics standpoint, there are multiple advantages. Stable, controlled flotation conditions can improve recovery rates of copper, which lifts overall yield. More stable water chemistry can reduce costs associated with corrosion, reagent overuse, or costly remediation of acidic effluent.
Firering Strategic Minerals plc (LON:FRG) is an emerging quicklime producer and critical minerals explorer, with operations in Zambia and West Africa.