Karara is the largest mining operation in the Mid West region and one of only two operating magnetite mines in WA. The mine is located 220 kilometres south-east of Geraldton in the Shire of Perenjori.
Karara has a multi-billion tonne mineral resource to sustain a long life (+30 years) operation. It comprises a large, complex and fully integrated mining, processing and transport logistics operation designed to produce 8 Mtpa of premium, high-grade magnetite concentrate for export to China for use in steelmaking.
Magnetite ore is mined from a large scale (15 m bench height) open pit mine in a traditional load and haul mining operation using conventional face shovels, large capacity (230 tonne) off-road haul trucks, a fleet of large diameter blast-hole drill rigs and a range of ancillary mobile mining equipment.
Magnetite ore known as Run-of-Mine (ROM) material is direct dumped by haul trucks from the mine into the primary crusher. Primary and secondary crushers crush the ROM ore to a product size of <60 mm. The crushed ore is then transferred to the Coarse Ore Stockpile (COS), which has a holding capacity of >500,000 tonnes of material for downstream processing.
Ore material from the COS is reclaimed by conveyor into a parallel train of two High-Pressure Grinding Rolls (HPGR’s), which grind the ore to a size of <4 mm.
Ore material of <4 mm from the HPGRs is pumped in a slurry to stage one magnetic separation. A high magnetic field allows separation of non-magnetic material to tailings. Magnetic material remains as a concentrate and is transferred to the primary grinding plant.
The primary grinding plant of four balls mills grinds the ore in slurry to fine particle sizes of <50 µm before further magnetic separation to produce a concentrated magnetite ore stream, with elevated Fe grades of ~58%.
Upgrading to final product specification occurs in the flotation circuit. Concentrate is filtered to achieve moisture levels <10% and a final, premium concentrate product with Fe grades of +65%. Product is transferred by rail to Karara’s Export Terminal at the Port of Geraldton.
The bulk of tailings material generated in the ore treatment process is filtered for dry tails stacking. There is reduced discharge of tailings to Karara’s wet tailings storage facility (TSF), or tailings dam. This enables us to maximise water recovery and minimise the environmental impact and footprint of tailings material.