Global mining and metals company Rio Tinto announced today an agreement with Australian environmental technology company Calix, including a commitment to invest more than A$35 million (USD$23 million) to support the construction of a new green iron demonstration plant that uses electric heating and hydrogen reduction to help decarbonize steelmaking.
Alongside the new agreement, Rio Tinto also announced that would pause its BioIron project, designed to test the effectiveness of a new technology to replace coal with biomass to enable a low-carbon ironmaking process.
Steelmaking is one of the biggest emitters of CO2 globally, with total greenhouse gas emissions (GHG) from the sector accounting for 7% – 9% of direct emissions from the global use of fossil fuels. As manufacturers globally aim to decarbonize their supply chains, demand for steel produced using fossil-free energy is expected to increase significantly.
Rio Tinto had introduced its plans for a BioIron R&D facility and pilot plant last year, with an anticipated A$215 million investment. The BioIron process uses raw biomass and microwave energy instead of coal to convert Pilbara iron ore to metallic iron in the steelmaking process. In the process, iron ore fines are mixed with raw biomass material, such as agricultural waste, and heated using a combination of gas released by the biomass and high-efficiency microwaves powered by renewable energy, to create metallic iron.
In its update, Rio Tinto said that it remains committed to the long-term potential of BioIron technology, and will continue its research and development, but noted that the current furnace design for BioIron requires additional development to minimize technical risks and to optimize its performance.
Rio Tinto Iron Ore Chief Executive Matthew Holcz said:
“The world needs low-emissions steel if it is going to decarbonise, and we continue to look at a range of ways Pilbara iron ores can help to do this as new technologies emerge.”
Rio Tinto’s new investment will support the construction of Calix’s Zero Emissions Steel Technology, or “Zesty,” which uses a combination of electric heating and hydrogen reduction to produce green iron, providing what the company said is the “lowest cost pathways to green iron and steel,” by minimizing hydrogen consumption, allowing the use of intermittent renewable energy sources, eliminating ore pelletisation, and enabling the use of fines and lower-grade iron ores.
The new Zesty plant, which will be constructed at the site previously earmarked for the BioIron facility, is designed to produce up to 30,000 tonnes per year of hydrogen direct reduced iron or hot briquetted iron from a range of iron ore sources, with a final investment decision expected in 2026. The project is also being supported by a grant of up to $44.9m from the Australian Renewable Energy Agency (ARENA), subject to matched funding being secured.
Under the new agreement, Rio Tinto will support the Zesty project to reach a Final Investment Decision through technical support, engineering services and advocacy, and, subject to project construction, will supply up to 10,000 tonnes of a range of Pilbara iron ores for use in plant commissioning and the initial testing phase of the project, as well as introductions to potential customers for downstream use of the Zesty product.
Calix Chief Executive Officer Phil Hodgson said:
“The Joint Development Agreement with Rio Tinto is a major milestone in the commercialisation of Zesty. It provides cash and hands-on support, including industry leading resources, expertise and market reach to progress the Zesty Demonstration project.”
