APU® ACID PURIFICATION UNIT
Electrolyte from the Copper Liberator cells is directed to the Spectrum Filter to remove suspended solids by an automated, back washable filter with a permanent media.
The filtered solution then flows through an Acid Purification system which consists of a proprietary ion exchange resin column where the electrolyte solution (sulphuric acid) is separated from the metal salts by the resin. A de-acidified metal stream flows to a treatment tank where chemical reagent is added to precipitate Nickel (and other metal) salts. The metal salts are dewatered and washed to produce a saleable nickel salt by-product.
The APU® is backwashed with water to produce a purified electrolyte stream for recycle to the copper tank house or leach circuit.