Rio Tinto has partnered with the Australian Renewable Energy Agency (ARENA) to study whether hydrogen can replace natural gas in alumina refineries to reduce emissions.

Rio Tinto will conduct a $1.2 MM feasibility study, equally funded with ARENA through a $580,000 grant, into using clean hydrogen to replace natural gas in the calcination process of refining at the Yarwun aumina refinery in Gladstone.

The study program includes work to be done at Rio Tinto’s Bundoora Technical Development Centre in Melbourne, where Rio Tinto’s in-house development capability has now been extended to hydrogen.

The study comprises two distinct work packages:

• Preliminary engineering and design study conducted to understand the construction and operational requirements of a potential demonstration project at the Yarwun alumina refinery.
• Simulating the calcination process using a lab scale reactor at the Bundoora Technical Development Centre.

Once complete, the study will inform the viability of a potential demonstration project. Rio Tinto has lodged patents for the hydrogen calcination process.

Rio Tinto is aiming to reach net zero emissions across its operations by 2050. Across the company, it is targeting a 15% reduction in absolute emissions and a 30% reduction in emissions intensity by 2030, from a 2018 baseline.

"If we can replace fossil fuels with clean hydrogen in the refining process for alumina, this will reduce emissions in the energy and emissions intensive refining stage of the aluminium supply chain," said ARENA CEO Darren Miller. "Exploring these new clean energy technologies and methods is a crucial step towards producing green aluminium."

“This study will investigate a potential technology that can contribute to the decarbonization of the Australian alumina industry. If successful, the technical and commercial lessons from Rio Tinto’s study could lead to the implementation of hydrogen calcination technology, not only in Australia, but also internationally.”