Copper–gold ore processing with ion exchange and SART technology

• Heap leaching of Cu–Au ore produces a PLS containing 1–2 ppm Au, and >1000 ppm Cu.
• PLS is treated by column ion exchange, using Dow’s gold-selective MINIX resin.
• Loaded resin is stripped with acidic thiourea solution.
• Au & Ag are electrowon on stainless steel mesh cathodes.
• Cu concentrations are controlled by passing part of the PLS through a SART process.

Anglo Asian Mining has developed a 50,000 oz Au/yr open pit gold mine at Gedabek in Western Azerbaijan. The deposit at Gedabek is a copper–gold porphyry, comprising both oxide and sulphide ore mineralisation, which is being mined at the rate of about 1 million tons of ore per year. Ore processing is by conventional cyanide heap leaching, which produces a pregnant leach solution (PLS) containing 1–2 ppm of gold, together with 1000 ppm or more of copper. The PLS is treated by column ion exchange, using Dow’s gold-selective MINIX resin. Loaded resin is stripped with an acidic thiourea solution, from which gold and silver are electrowon on to stainless steel mesh cathodes. Copper concentrations in the leach solutions are controlled by passing part of the PLS flow through a SART process, where the acronym stands for “Sulphidisation, Acidification, Recycling and Thickening”. The product from the SART process is a copper/silver sulphide precipitate, which is thickened, filtered and dried and then sold for copper smelting.

Flowsheet of Anglo Asian Mining’s process for treatment of gold/copper ore with heap leaching, CIX and SART technology.Figure optionsDownload as PowerPoint slide