Roy Hill is a low phosphorus, Marra Mamba iron ore deposit located in the Pilbara – close to Asia and in one of the world’s premier iron ore provinces.

The Marra Mamba Iron Formation is the basal member of the Hamersley Group in Western Australia and is host to major iron-ore deposits in its upper Mt Newman Member.

Roy Hill is an owner operator, conventional open pit, drill and blast, truck and excavator bulk mining operation.

Roy Hill’s purpose built, world class mine processing plant utilises low risk, proven technology to process 55Mtpa (Wet) of lump and fines iron ore and is the largest single feed processing plant in the Pilbara region.

A wet processing and beneficiating model has been selected, as approximately 70 per cent of the bedded ore resource is below the water table and contains wet, sticky plastic, clay rich shale bands, which are difficult to handle in a dry crushing and screening process.

Feedstock for the processing plant will come either from Run of Mine (ROM) blended stockpiles (60%) or direct from the mining pits (40%), delivered to three primary and secondary crushing plants located at the edge of the mining pits.

The primary and secondary crushing plants are designed to crush ore to 100mm. Crushed ore from these plants will be delivered by overland conveyors to a 250,000 tonne Coarse Ore Stockpile which acts as a blending station and buffer to the processing plant.

The processing plant consists of six individual scrubbing, screening and de-sanding circuits.

The wet scrubbing units are used to break down the sticky clays attached to the ore, into a fine suspended clay fraction suitable for subsequent wet beneficiation. Beneficiation is the process of separating the valuable material from the waste material.

After passing through the wet scrubber units the ore is fed into the screening circuit. The screening circuit sorts the ore into Lump and Fines products. Lump ore produced from the processing plant will range in size from 8mm to 40mm, while Fines ore will be less than 8mm in size.

This top deck of the screen separates oversize material (>40mm) which is then tertiary crushed for further size reduction. The lower deck separates material into Lump product (>8mm to <40mm) which is delivered via conveyors straight to the lump product stockyard.

Sub 8mm ore is transferred to a single deck wet banana screen, which separates the ore into Fines product (<8mm to >1mm) with the undersize material (<1mm) pumped to the de-sanding circuit for gangue (impurities) removal.

Five de-sand modules operate in parallel in this circuit with each module consisting of cyclone classification, up current classification and spiral concentration units which use water and gravity movement to filter and remove gangue material.

Each module contains both rougher and scavenger spirals. Rougher spirals produce three products; concentrate, middlings and tailings, with concentrate directed to vacuum filter belts for de-watering and middlings and tailings material sent to the scavenger spirals.

Scavenger spirals recover any iron minerals that is contained in the middlings and tailings material. Concentrate from the scavenger spirals is sent to the vacuum filter belts for de-watering and tailings are pumped to the residue thickener for disposal to the tailings storage facility.

De-watered ultra-fines product is then recombined with coarse Fines on the Fines transfer conveyor and delivered to the mine stockyard.