Queensland Pacific Metals Ltd (ASX:QPM) welcomes successful hematite pellet test-work completed with the CSIRO that generated samples with properties suitable for blast furnace iron making.
The testing by CSIRO’s Carbon Steel Materials Group in Queensland produced hematite pellets with 62.84% iron content, reducibility index of 60.3%, a low Temperature Reduction Disintegration Index of 2.9% and compressive strength of 2493N.
What’s more the pellets were below typical thresholds for impurities such as SiO2, P and S that attract penalties in the iron ore market.
Attractive feed option
The test-work by Australia’s national science agency, CSIRO, provides important technical information for the final design of the pellet plant in QPM’s TECH Project, which is expected to produce more than 600,000 tonnes per annum of hematite pellets in Stage 1
It makes the hematite product produced at the TECH Project an attractive feed option for steel mills, particularly when combined with the world-class ESG credentials of the TECH Project, which will be important for marketing and securing potential offtake partners.
Based on this important work, QPM’s preference for the hematite product is to produce pellets.
About the tests
The laterite ore to be processed by QPM at the TECH Project has a typical iron grade of around 42%.
The DNi ProcessTM to be used dissolves iron into solution and recovers it as a high-purity hematite precipitate. The hematite product can then be agglomerated into a material suitable for direct feed to a blast furnace.
In 2022 QPM engaged the CSIRO to undertake the test program, utilising hematite product produced from previous test-work including pilot plant operations.
After an initial material characterisation phase, CSIRO tested agglomeration of the hematite product using two widely used approaches – pelletisation and sintering.
Pelletisation tests
Hematite pellets with properties suitable for direct feed to a blast furnace were produced under various conditions, using industrial standard methods.
QPM is engaging with pellet plant suppliers to complete the process design and capital estimation of the commercial plant.
Chemical and physical analyses of the pellets produced by CSIRO were completed, with results presented in the table below.
Chemical and physical analyses of pellets.
Sinter test-work
The QPM hematite product was added in increasing concentrations of up to 15% into a base blend of iron ores to determine what effect the product could have on sintering (see table below).
The QPM hematite has a relatively fine particle size, so magnetite concentrates were initially substituted in Blends 2 and 3 to give a comparison between materials of a similar size. A generic Asian steel mills blend was used as the base blend.
The results showed that the green bed permeability improved with increasing amounts of QPM hematite in the blend.
The sinter’s Reducibility Index (RI), Tumble Index (TI) and Mean Product Diameter all improved with the addition of the QPM hematite, while there was a marginal increase in Reduction Disintegration Index (RDI).
Green bed permeability (L) and sinter characteristics (R).
However, the improvement in green bed permeability did not correspond to an improvement in sinter
productivity likely due to the reduced heat transfer and internal melting in the granulated particles within the bed. This resulted in a 28% reduction in sinter productivity and a 2.7% increase in fuel rate.
Sinter characteristics.
CSIRO’s test work demonstrated that increasing hydrated lime (HLM) concentrations from 1.5% to 4% in the sinter blend did overcome the sinter productivity loss, returning it to 40t/m2/d.
There were marginal decreases in RI and TI as well as slight improvement in RDI for sinter with increased hydrated lime.
Marketing appointment
In order to drive sales of co-products produced at the TECH Project, the company has recently appointed Geoff Beros as technical marketing manager.
Beros previously worked for Fortescue Metals Group (ASX:ASX:FMG) as senior manager technical marketing.