Solution Treatment
In the GEOLEACH™ processing of base metal concentrates, the solution bleed stream is the feed to downstream metals recovery processes. The flow rate of the bleed stream is selected to maintain the concentration of the metal to be recovered at the optimum for downstream processing. Solutions are circulated via an ILS pond to allow maximization of grade and better control of the acid balance. The development of the solution handling system is highly dependent on the ore type, its leaching kinetics and the pad configuration.
In some cases the bleed stream may require purification prior to metal recovery to remove iron or arsenic. The purification is conducted in a conventional neutralization circuit utilizing limestone to form stable metal precipitated while leaving the desired metal in solution for subsequent recovery.