Copper Oxide Ore: Leach–SX–EW Flowsheet and Equipment List

Oxide copper ores do not concentrate well by flotation, so the default route is direct leaching followed by solvent extraction and electrowinning. The flowsheet below is the configuration we build most often at pilot and small commercial scale.

Route

Step	Purpose	Equipment	Key parameter
1. Comminution	Liberate oxide minerals	Jaw crusher + ball mill	P80 75–150 µm
2. Leaching	Dissolve copper	Agitated tanks or vat, PP/316L	pH 1.5–2.0, 10–20% solids, 2–6 h, ambient–60 °C
3. Solid–liquid separation	Clarify pregnant leach solution (PLS)	Thickener + filter press	< 50 ppm solids to SX
4. Solvent extraction	Concentrate and purify copper	Mixer-settlers, 2 extraction + 1 strip	O/A 1:1–2:1, pH 1.8–2.2, 40% extractant
5. Electrowinning	Produce cathode	EW cell, Pb or MMO anodes, SS cathodes	300–400 A/m², 35–45 °C, 150–180 g/L H₂SO₄
6. Spent electrolyte return	Close the loop	Pumps, tanks	Bleed to control impurities

Where these plants fail

Filtration. Sending 200 ppm solids to the settlers produces crud within weeks. Budget for proper filtration, not a settling pond.

Acid balance. Oxide ores consume acid in proportion to gangue. If the gangue is carbonate, acid consumption can exceed the value of the copper — run the acid consumption test before committing.

Bleed. Without a bleed, iron, manganese and chloride accumulate until current efficiency collapses. Design the bleed at the start.

Scaling down

At pilot scale the same route runs in tanks of 50–500 L with a small mixer-settler bank and a 50–200 A rectifier. The chemistry does not change; the hydraulics do, and that is where pilot data is most valuable — dispersion band behaviour, crud formation and filtration rate.

Send your head assay, acid consumption test and target cathode output, and we will size the train and the EW circuit.