As the race to 2030 net zero emission targets draws near, the Australian Government has today announced its intention to trial hydrogen calcination technology at Rio Tinto’s (RIO) Yarwun alumina refinery in Gladstone, Queensland.
On behalf of Canberra, the Australian Renewable Energy Agency (ARENA) will award $32.1 million to Rio and Japan’s Sumitomo Corporation to fund the first-of-its-kind hydrogen calcination trial.
The total cost of the Yarwun Hydrogen Calcination Pilot Demonstration Program is valued at $111.1 million and will host a 2.5 megaWatt electrolyser to supply hydrogen, and a retrofit of one of the refinery’s calciners to operate with a hydrogen burner.
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,” he said.
Carbon-intensive refining process
The project is aimed to reduce emissions caused by alumina refining, as they contribute to three per cent of Australia’s greenhouse gas emissions.
Australia is the world’s largest exporter of alumina, the mineral feedstock for aluminium production, with the industry contributing $7.5 billion to the nation’s GDP.
According to ARENA, calciners are crucial in the alumina refining process, as they utilise high temperatures to remove chemically bound water from alumina crystals.
However, conventional calcination methods rely on fossil fuels for process heat, leading to significant emissions that account for approximately 30 per cent of emissions associated with alumina refining.
Exploring cleaner fuels
Hydrogen calcination, on the other hand, offers several advantages – one of which is the production of high-purity steam.
Unlike the contaminated steam generated through fossil fuel calcination, the steam produced during hydrogen calcination can be recycled and utilised in other stages of the refining process.
“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,” Mr Miller added.
“ARENA will continue to support projects at this scale as we develop other larger programs, such as Hydrogen Headstart.”
Private sector collaboration
The demonstration follows a successful feasibility study conducted by Rio in 2021, supported by ARENA through a $580,000 grant.
The role of the Sumitomo Corporation will be to 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 tonnes of hydrogen annually.
Rio will conduct a series of tests of the hydrogen calciner under differing operating conditions to validate suitability and performance, with the end date of the program in August 2028.
If successful, the project will demonstrate the viability of hydrogen calcination and pave the way for adoption at mass scales across other alumina refineries.
ARENA’s Alumina Decarbonisation Roadmap published last year identified hydrogen calcination as one of four technologies that could reduce emissions from Australia’s alumina refineries by up to 98 per cent.