Overview
Beneficiation is the process of improving the quality of ores by separating valuable minerals from waste material. Traditional beneficiation uses physical methods such as crushing and magnetic separation. However, these methods can create large amounts of waste (tailings), which can constitute 40-70% of input material, be costly to manage, and contain some of the iron ore itself.
This project explores a novel method to remove impurities from iron ores and thus upgrade low-grade iron ore (LGIO) quality by using byproducts from seawater desalination – specifically, the salty brine left over after removing fresh water – as the source of reagents.
The goal is to upgrade LGIOs and tailings for direct reduced iron (DRI) production, which is particularly relevant for hematite and goethite ores from the Pilbara region in Western Australia. DRI has the potential to significantly lower Scope 3 emissions (indirect emissions generated during the production and downstream use of iron ore, including processing into steel), improve resource efficiency, and support the green hydrogen economy.
The project also seeks to unlock substantial economic and environmental benefits. Australia’s iron ore production is projected to exceed 1 billion tonnes annually by 2024, with more than one-third comprising LGIO. By upgrading this LGIO, the project taps into a multibillion-dollar market while also generating high-value byproducts.
This project received funding from the Australian Renewable Energy Agency (ARENA) to expand and accelerate its impact to reduce emissions from Australia’s iron and steel supply chain. Additional financial and in-kind support for the project was also received from the Minerals Institute of Western Australia (MRIWA) and Curtin University (more information on funding here).
Project Details
This project aims to create a scalable hydrometallurgical process to upgrade LGIO (47-56% iron) to high-grade iron ore (63-67% iron), a critical requirement for producing low-carbon DRI. The approach – Brine-derived Alkaline Leaching of Iron Ores, or the BALIO process – uses reagents extracted from seawater desalination brines, eliminating waste while producing valuable byproducts such as lithium salts, zeolites (used in water purification), silica and fertiliser minerals.
Following an initial stage to confirm the feasibility of the technique and develop a detailed business case, the project comprises two further stages:
- Core research (3 years): this stage focuses on developing and refining the process to ensure it is both economically viable and scalable through (a) laboratory and mini-plant experiments to integrate the process steps; and (b) a detailed technoeconomic analysis to identify risks and determine the research required to develop the technology. Activities include conducting thermochemical simulations, characterising ores and testing alkaline leaching methods to remove impurities. The research team will also recover byproducts, assess the economic and environmental feasibility, and validate the upgraded ore for DRI production. This stage includes recruiting postgraduate students to build expertise and research capacity for the iron and steel sector.
- Research commercialisation (2 years; subject to funding approval): this stage will advance the work by designing a pilot plant and estimating costs for large-scale implementation. It will also integrate findings from lab tests into detailed engineering designs and simulations, supporting decisions on commercial-scale adoption of the technology.
Together, these stages aim to establish a viable pathway for upgrading iron ore in an environmentally sustainable and economically competitive manner.
HILT CRC Milestones
1.2 Producing green iron products from hematite/goethite ores
Research Areas
- Low-grade ore beneficiation
- Removal of silica and alumina from low-grade hematite/ goethite ores (desliming)
- Technology and methods to manage variable sources of renewable electrical energy within a process
- Low-carbon iron exports from direct shipping ores
Project Outcomes
Stage 1: core research
- Feasibility study.
- An experimentally validated process to hydrometallurgically upgrade LGIO and produce value-added by-products.
- Demonstrated key unit operations, e.g. technologies used in reagent generation (NaOH and HCl solutions), lithium removal, leaching of impurities and byproduct generation.
- An understanding of the baseline design requirements for a sub-pilot plant with considerations for a full-scale plant.
Stage 2: commercialisation
- A detailed understanding of the design and cost of establishing a sub-pilot plant.
- Minimisation of technology risk for industry partners seeking to adopt the proposed process for upgrading iron ore.
Project Benefits
- Enabling green steel production from LGIO via a hydrogen-based direct reduced iron–electric arc furnace (DRI-EAF) route.
- Potential to abate up to 100 million tonnes of CO2 annually from the smelting of Australian iron ores with blast furnace technology when using the hydrogen-based DRI-EAF route instead.
- Removing impurities from LGIO reduces weight by 5–8%, decreasing CO2 emissions from transport and shipping.
- Valuable byproducts such as lithium salts, zeolites and fertiliser minerals, reducing waste and creating additional revenue streams.
- Beneficiation costs offset by utilising reagents derived from seawater brines.
- Elimination of waste disposal challenges associated with alternative caustic leaching methods, which produce environmentally harmful waste streams requiring costly treatment.
Download the Project Summary
Case study
Watch Project Leader Dr Lina Hockaday explaining the project: