The Australian Renewable Energy Agency (ARENA) has announced AU$11.3 million in funding to Alcoa of Australia Ltd (Alcoa) to demonstrate technology that can electrify the production of steam in its alumina refining process using renewable energy. The first-of-its-kind deployment of Mechanical Vapour Recompression (MVR) in Australia is planned to be undertaken at Alcoa’s existing Wagerup Alumina Refinery in Wagerup, Western Australia (WA).
Australia is the world’s largest exporter of bauxite and one of the largest exporters of alumina accounting for 15 percent of global alumina refining capacity. Alumina refining is an energy-intensive process that uses high-pressure steam to produce the heat required to process bauxite into alumina.
Alumina can then be converted to aluminium in a smelting process. In 2019, alumina refining accounted for over 14 million tonnes of carbon dioxide (CO2) in Australia, which represents approximately 24 percent of Australia’s scope 1 manufacturing emissions.
Investigate the feasibility of MVR
Approximately 70 percent of the total fossil fuels consumed in alumina refining relates to the production of steam in boilers. Mechanical Vapour Recompression (MVR) is a potential alternative to produce steam using renewable electricity.
MVR recompresses waste steam that would otherwise be exhausted to the atmosphere and recycles it in the refining process. This technology has the potential to improve efficiency, reduce costs and reduce emissions.
Alcoa’s main objective for the project, the total cost of which is AU$28.2 million, is to demonstrate the technical and commercial feasibility of using MVR powered by renewable energy to produce process heat.
Stage 1 of the project will investigate the feasibility of integrating MVR at the refinery. If proven feasible, for Stage 2 of the project, Alcoa will deliver a 3 MW MVR module, powered using renewable energy at the Wagerup Alumina Refinery.
Already, Alcoa is the world’s lowest carbon intensity alumina producer, and the application of MVR if proven successful, can be an important step forward in further reducing greenhouse gas emissions. With MVR, there is potential to significantly reduce carbon emissions from our refining operations and in the aluminium industry more broadly, said Eugenio Azevedo, VP for Continuous Improvement and Refining Technology at Alcoa.
In line with Government policy
The Australian Government’s first Low Emissions Technology Statement highlights the importance of developing a low emissions steel and aluminium industry to help reduce emissions and stimulate economic activity.
Innovation in metals refining can improve the competitiveness and emissions intensity of Australia’s steel and aluminium production.
ARENA CEO Darren Miller said this exciting project was a significant step towards making low emissions alumina, and an important step towards decarbonising metals production.
It’s great to see companies like Alcoa take the initiative to create a pathway to reduce their emissions in what is an energy-intensive hard to abate process. This technology represents an opportunity to electrify a refining process that is currently powered by fossil fuels using a renewable solution that addresses our investment priority of helping the industry to reduce emissions, as well as the Government’s Technology Investment Roadmap. This is an important step on the pathway towards green aluminium in Australia, commented Darren Miller.