PERTH (miningweekly.com) – The Australian Renewable Energy Agency (Arena) has announced a A$32.1-million grant for Rio Tinto and Sumitomo Corporation to trial hydrogen calcination technology at the Yarwun alumina refinery in Gladstone, Queensland.

The A$111.1-million Yarwun hydrogen calcination pilot demonstration programme will be the first-of-its-kind deployment of hydrogen calcination in the world. The project is intended to reduce emissions in alumina refining, which currently contributes roughly 3% of Australia’s greenhouse-gas emissions.

The project will consist of a 2.5 MW on-site electrolyser to supply hydrogen and a retrofit of one of the refinery’s calciners to operate with a hydrogen burner.

The trial is expected to produce the equivalent of about 6 000 t/y of alumina while reducing Yarwun’s carbon dioxide emissions by about 3 000 t/y.

Converting the entire plant to green hydrogen could reduce emissions by 500 000 t/y, which is the equivalent of taking about 109 000 internal combustion engine cars off the road.

Construction will start in 2024. The hydrogen plant and calciner are expected to be in operation by 2025.

“This pilot plant is an important step in testing whether hydrogen can replace natural gas in Queensland alumina refineries,” Rio Tinto aluminium Pacific operations MD Armando Torres said.

“At Rio Tinto we have put the energy transition at the heart of our business strategy, and this is one of the ways we’re working towards decarbonising our operations. We are proud to be developing this new technology here in Gladstone, in partnership with Sumitomo Corporation, and with support from Arena.”

Sumitomo Corporation will own and operate the electrolyser at Rio’s Yarwun site and supply the hydrogen to Rio directly. The electrolyser will have a production capacity of more than 250 t/y of hydrogen.

Rio Tinto will conduct a series of tests of the hydrogen calciner under differing operating conditions to validate suitability and performance.

Sumitomo Corporation energy innovation initiative director Seiji Kitajima said the company was excited to be delivering this hydrogen project together with Rio Tinto as its long-term partner with the support of Arena.

“Demonstrating real-world applications of hydrogen in industrial settings with motivated partners is essential to reducing carbon emissions and working toward our company’s vision of achieving carbon neutrality by 2050. Through this demonstration, Sumitomo Corporation aims to venture into the commercialisation project to contribute to Rio’s decarbonisation.

“Sumitomo Corporation is proud to be working on yet another hydrogen project in Australia and contributing to Australia’s own emission reductions goals.”

Arena CEO Darren Miller said the project was an important step in the development of hydrogen calcination and the decarbonisation of the alumina production process. 

“This world-first pilot looks to prove a promising technology for decarbonising one of our most emissions-intensive industries,” Miller said. 

“Having already backed an encouraging feasibility study, we’re excited to be working with Rio Tinto and Sumitomo Corporation to build on that success and trial hydrogen calcination in the field.

“If this pilot project is successful, it could be a game changer for Australian alumina production, paving the way for deployment across the industry, and underscoring the importance of low-cost green hydrogen to decarbonise our largest industrial emitters. Arena will continue to support projects at this scale as we develop other larger programmes, such as Hydrogen Headstart.”

If successful, the project will demonstrate the viability of hydrogen calcination and pave the way for adoption at scale across other alumina refineries. 

Climate Change and Energy Minister Chris Bowen said innovative technology like this was critical for decarbonising heavy industry.

“The government’s announcement today is about backing the future of our jobs-rich aluminium industry, which brings in around A$14-billion in export revenue each year and employs more than 17 000 Australians.

“Australia is the world’s largest exporter of alumina and cutting emissions from our alumina refining will ensure this industry can continue to thrive in a decarbonising global economy – where 139 countries have net zero by 2050 commitments.

“This technology could also pave the way for other hard-to-abate sectors to reduce their emissions,” Bowen said.

The demonstration follows a successful feasibility study conducted by Rio Tinto, which Arena supported with a A$580 000 grant in 2021.

Australia is the world’s largest exporter of alumina, the mineral feedstock for aluminium production, with the industry contributing A$7.5-billion to the nation’s gross domestic product. Arena has been investing in projects to reduce emissions from the aluminium value chain since 2021. This includes providing funding to Alcoa to investigate electric calcination and trial mechanical vapour recompression, two further technologies identified in the Alumina Roadmap.