Wedoany.com Report-Nov. 18, Rio Tinto has entered into a joint development agreement with Australian technology company Calix to advance the proposed Zesty green iron demonstration plant in Kwinana, Western Australia. The company announced the partnership on Monday.

Rio Tinto Iron Ore CE Matthew Holcz says the pilot could help progress a pathway for Pilbara ores in low emissions steelmaking.

The planned facility will be located at the same site originally selected for Rio Tinto’s BioIron research and development facility. Following a detailed technical review, Rio Tinto has decided to pause further design work on the BioIron furnace until additional improvements are completed to reduce risks and enhance performance. The company remains committed to the long-term development of the BioIron process.

The BioIron technology, developed over the past ten years by Rio Tinto’s steel decarbonisation team in collaboration with the University of Nottingham and Metso, uses raw biomass such as agricultural residues as a reducing agent and requires significantly less electricity than hydrogen-based steelmaking methods.

Under the new agreement, Rio Tinto will provide approximately A$35 million in funding and technical support for the Zesty project, which has also received backing from the Australian Renewable Energy Agency (ARENA). Calix has secured a separate conditional ARENA grant of up to A$44.9 million.

The Zesty process employs electric heating combined with hydrogen reduction to produce lower-emission iron. It is designed to process Pilbara iron ores, including lower-grade material. The demonstration plant, if approved, will have capacity to produce up to 30,000 tonnes per year of direct-reduced iron or hot-briquetted iron.

Rio Tinto Iron Ore Chief Executive Matthew Holcz stated that the partnership supports progress toward lower-emission steelmaking pathways using Pilbara ores, while development of the BioIron technology will continue in parallel.

Rio Tinto will supply engineering expertise to help advance the project toward a final investment decision targeted for 2026. Upon approval, the company will provide up to 10,000 tonnes of Pilbara ore for initial testing and commissioning and will assist in connecting the project with potential future customers.

The agreement grants Rio Tinto a non-exclusive, perpetual global licence to use the Zesty technology for commercial purposes, including the right to sub-licence to affiliates and customers and to serve as a non-exclusive global marketing agent.

The Kwinana location benefits from existing infrastructure, including utilities and port access, and is situated near the NeoSmelt facility, where Rio Tinto and partners are exploring downstream processing options with ARENA support.

Calix Chief Executive Phil Hodgson said the joint development agreement provides both financial resources and strategic support from a leading industry participant as the Zesty project moves into detailed engineering ahead of the final investment decision.