Overview
The iron and steel industry faces increasing pressure to adopt sustainable processes and use low-grade iron ores effectively. Conventional beneficiation methods struggle to produce the high-grade iron ore needed for electric arc furnaces, while the declining availability of premium ore deposits in Australia necessitates innovative, low-carbon technologies that are efficient, cost-effective, and require minimal energy and water.
Thermally assisted beneficiation methods, particularly low- to mid-temperature processes, show promise for achieving high-grade concentrate and mass yields using renewable energy. These methods also reduce the amount of slag (waste material containing impurities removed from ore), improve pellet properties, and support hydrogen direct reduced iron (H2DRI) processes.
High-flux radiation technology has demonstrated potential at lab scale, but scaling up and studying key variables (e.g. heating rates and reduction conditions) are critical for commercialisation. It is also crucial to understand how these beneficiated products perform in H2DRI and pellet production.
The alumina sector also faces decarbonisation challenges. High levels of carbon found in Australian bauxite (total organic carbon, or TOC) reduce the efficiency of the Bayer process (refining bauxite ore to produce alumina), limiting yield and product quality. Advances in thermally assisted technologies, such as high-flux radiation methods, show promise for reducing carbon while maintaining alumina extraction.
This project aims to address these challenges, advancing Australia’s ability to develop low-carbon solutions for the iron/steel and alumina industries.
Project Details
This project builds on findings from HILT CRC’s previous research (RP1.008) to advance the development of thermally assisted beneficiation technologies for low-grade and complex iron ores. It aims to:
- Upscale a novel thermal beneficiation technology that uses high-flux radiation powered by green energy sources, such as hydrogen combustion, to upgrade iron ores.
- Assess the suitability of these beneficiated iron ore products for use in H2DRI and pellet production through mineralogical analysis and testing.
At sub-pilot scale (up to 10 kg/hr), the project will demonstrate the technology’s ability to dehydroxylate goethite, enhance magnetic separation and potentially recover valuable byproducts. This work will generate new data to refine technoeconomic models and inform optimal processing conditions, bringing the technology closer to industrial application.
Beyond beneficiation, the project will evaluate how the upgraded iron ores perform in downstream processes such as green DRI and pellet production. It will also explore potential applications for bauxite ores in the alumina sector, focusing on removing carbon to improve refining efficiency.
HILT CRC Milestones
- 1.1 Producing green iron products from magnetite
- 1.2 Producing green iron products from hematite/goethite ores
- 1.4 Low-carbon heat for the hydrometallurgical process component of alumina refining
Research Areas
- Decarbonising production of green iron products from magnetite ores
- Low-carbon pellet production
- Low-carbon iron exports from direct shipping ores
- Low-grade ore beneficiation
- Thermal pre-concentration and beneficiation processes using low-carbon energy
Project Outcomes
- Evaluation of reductive roasting (a high-temperature process that improves ore quality) for increasing magnetite content in low-grade iron ores and improving magnetic separation.
- Demonstration of a novel ore roasting technology at sub-pilot scale using moving bed technology.
- Improved accuracy of process modelling and technoeconomic analysis through new data.
- Assessment of the suitability of beneficiated iron ore products for use in H2DRI and pellet production through mineralogical analysis and testing.
- Expanded understanding of the potential application of the roasting technology for bauxite beneficiation, including TOC removal and alumina availability.
- A detailed plan for scaling up the technology.
Project Benefits
- Development of innovative process options for reducing gangue (non-metallic minerals) and/or TOC levels, enabling products with lower carbon footprints and improved process efficiency.
- Demonstration of the potential to produce high-grade iron ore feedstock suitable for H2DRI and green pellet production, meeting electric arc furnace requirements.
- Advancement of thermally assisted beneficiation technology, supporting technically feasible engineering solutions for the iron/steel and aluminium sectors.
- Direct benefits to HILT CRC’s partners in the alumina industry through the application of roasting technology for bauxite, improving refining efficiency and sustainability.
- Contribution to industry-wide adoption of low-carbon beneficiation processes, enhancing the competitiveness of Australian iron and bauxite ores in global markets.