Analyzing Gold and Silver Recovery from Copper Smelting to Anode Slime Treatment

Precious metals, gold and silver, are valuable by-products of processing copper sulfide concentrates, significantly enhancing the revenue of custom copper smelters and miners, especially during challenging market conditions characterized by low treatment and refining charges. They gradually accumulate in matte, copper blister, copper anode, and copper anode slime (CAS), treated at the precious metal plant. While various processes and technologies can influence precious metal yields, recovery rates for gold and silver are often underreported during copper smelting and CAS treatment. In this study, we attempt to predict gold and silver first-pass recovery rates across different processing steps, considering mechanisms of precious metal loss. We utilize commonly reported data in the literature such as the mass of phase streams, slag tapping temperature, copper physical loss in slag, precious metal partition coefficients, the slag bulk Fe/SiO₂ ratio, and matte copper percentage. Additionally, we evaluate different processing techniques for CAS, with a focus on the first-pass recovery of precious metals. Our findings reveal integrated processing routes that maximize the gold and silver recovery rates, providing valuable insights for optimizing techniques and enhancing economic viability.