Iron Road Ltd (ASX:IRD) welcomes the completion of an independent technical review of the ore processing flow sheet for Central Eyre Iron Project (CEIP) that verifies the ore processing flowsheet.
The review has been completed by specialist consulting firm to the iron ore and steel industries, Metalytics.
This process flowsheet is designed to deliver a high-grade iron product (66.6% iron) which is competitive with existing global magnetite and hematite concentrates.
The coarse-grain structure of CEIP in-situ gneissic ore facilitates beneficiation, especially compared with fine-grained banded iron formation (BIF) magnetite projects in Western Australia.
Metalytics' independent review verifies the process flowsheet design used by Iron Road in previous feasibility and optimisation studies to achieve expected ore processing outcomes.
Metalytics key findings
A key finding of the Metalytics report is that the coarse grain size and moderate hardness of the CEIP ore make it possible to reject 60% of the run-of-mine (ROM) mass at the Rougher Magnetic Separation (RMS) step, ie after semi-autogenous grinding to 3-millimetre particle size.
Consequently, only the remaining 40% mass flow enters a ball mill circuit for grinding and this 40% stream has an average iron grade of around 27% iron, which is well within the usual range for magnetite mines.
The resultant material is then beneficiated to the finished concentrate product at a mass recovery of 37% and an iron recovery of 90% – levels that are, respectively, favourable, and comparable to the existing or under-construction Australian and Canadian high-grade iron concentrate projects.
Low chemical variability of CEIP gneissic ore complements the consistency of its mineralogical and physical characteristics providing confidence of efficient processing performance in producing high-grade iron concentrate of consistent quality.
As per the report, these distinct features have important implications for CEIP’s projected capital and operating costs and highlight substantial reductions in the cost of electric power for both coarse and fine grinding that would be required with flow sheets to treat comparable tonnages.
CEIP concentrate marketability
Metalytics’ review indicates that the proposed saleable product would have a unique grain size distribution among traded seaborne iron ore products, positioned between the ultra-fine sizing of typical pellet feed concentrates and the coarser sizing typified by sinter feed concentrates, exhibiting certain sizing similarities to domestic Chinese iron ore concentrates.
The planned particle size distribution (PSD) for 66.6% iron CEIP magnetite concentrate lies between those two generic product types and more closely resembles domestic Chinese iron ore concentrates.
This allows Iron Road and CEIP partner(s) a degree of marketing flexibility in negotiating CEIP concentrate offtake agreements with Chinese and non-Chinese steelmakers.
Premium high-grade iron ore products reduce energy consumption and CO2 emssions along with other pollutants and dust, and increase blast furnace productivity and reduce slag generation.
China, the world’s dominant iron ore market, is continuing to push its environmental policy and regulatory agenda to reduce pollution, energy consumption and CO2 emissions.