PERTH (miningweekly.com) – The federal government will provide more than A$500 000 in funding a study investigating the feasibility of using renewable hydrogen instead of natural gas to process alumina, helping to reduce emissions across the aluminium supply chain.
Mining giant Rio Tinto will conduct a A$1.2-million feasibility study, equally funded with the Australian Renewable Energy Agency (ARENA) through a 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’s Bundoora Technical Development Centre in Melbourne, where Rio’s in-house development capability has now been extended to hydrogen.
“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. Exploring these new clean energy technologies and methods is a crucial step towards producing green aluminium,” ARENA CEO Darren Miller said.
“This study will investigate a potential technology that can contribute to the decarbonisation of the Australian alumina industry. If successful, the technical and commercial lessons from Rio’s study could lead to the implementation of hydrogen calcination technology, not only in Australia, but also internationally.”
Rio Tinto Aluminium Pacific Operations acting MD Daniel van der Westhuizen said that the study was a step towards reducing refinery emissions and one that has the potential to play an important part in Rio’s commitment to decarbonisation.
“We’re investing in work that needs to be done, not only to decarbonise one of our sites, but also to help provide a lower-emissions pathway for Rio Tinto and the global aluminium industry.
“We recognise we are on a long road towards reducing emissions across our operations and there is clearly more work to be done. But projects such as this are an important part of helping us get there.”
The study comprises two distinct work packages, including a preliminary engineering and design study conducted to understand the construction and operational requirements of a potential demonstration project at the Yarwun alumina refinery.
The study would also include 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 has lodged patents for the hydrogen calcination process.
Rio 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.
Alumina refining accounts for approximately 24% of Australia’s direct, non-electricity (scope 1) manufacturing emissions, or 14-million tonnes annually.
If feasible, the technology has the potential to significantly reduce emissions from the energy-intensive industry and lock in its long-term future, said Minister for Energy and Emissions Reduction Angus Taylor.
“The aluminium industry is a valuable sector of our economy, both in terms of export earnings and as an employer of more than 22 000 Australians. It is our sixth largest export by value, earning A$12.7-billion in 2019-20. Australia is also the world’s largest exporter of alumina and accounts for around 15% of global refining capacity.
“Securing the future of industries like this is essential for our long-term economic prosperity. That’s why we’re partnering with the private sector and backing the development of low emissions technologies, including hydrogen and low emissions alumina production. Replacing higher-emitting alternatives with cleaner energy sources will reduce the carbon footprint of our energy-intensive industries and enable them to continue operating for decades to come.”