Project Background
An East African iron ore miner needed to upgrade low-grade hematite-magnetite ore (32% Fe head grade) into a saleable 65% Fe concentrate for the regional steel industry. The site has no grid power, so the plant had to be designed for diesel generator operation with optimized power consumption.
Process Design
WSHT developed a flowsheet combining magnetic separation at coarse and fine sizes:
- Three-stage crushing: jaw + cone + HPGR (high pressure grinding rolls) reducing to -3mm
- Wet rod milling in open circuit, then ball milling in closed circuit (P80 = 80μm)
- Stage 1: low-intensity magnetic separation (LIMS) on rod mill discharge
- Stage 2 & 3: LIMS on ball mill cyclone underflow and final concentrate cleaning
- Tailings thickening & water recovery circuit
Equipment Supplied
Complete crushing & grinding package: C130 jaw crusher, GP220 cone crusher, two Polycom HPGR rolls, MBZ2136 rod mill, MQG2700×4500 ball mill, 6 magnetic separators, 4 thickeners, full pumping and pipeline network.
Civil, Power & Installation
Project included 8,000 m² of concrete works, 2,400 t of steel, a 6 MW diesel power plant, and a 35 km raw water pipeline from a nearby river. Installation completed by a 90-person WSHT site team in 7 months.
Performance & Results
Plant ramped up to design throughput within 4 weeks of commissioning. Final concentrate grade 65.3% Fe at 82% mass recovery, exceeding the client's target. Power consumption 18% below the original design estimate.