Mining giant looks to limit emissions by electrifying refining process

A South West mining giant is looking to limit emissions by electrifying its heavily polluting refining process with help from a $4.4 million grant.

South 32 received funding from the Australian Renewable Energy Agency in order to support the development of steam electrification pathways at the Worsley Alumina Refinery in the South West.

The alumina refining industry is the country’s biggest user of industrial process heat, collectively responsible for about 15 million metric tonnes of CO2 emissions in 2021 — 3 per cent of Australia’s total green house gas emissions that year.

Currently, close to 70 per cent of these emissions are produced from steam production in the alumina refining process, fuelled by fossil fuel sources such as coal and gas.

With the sector identified as a hard-to-abate polluter finding a method to reduce emissions is needed.

The identified options to reduce these emissions include electric boilers, which generate steam directly using an electrode, and mechanical vapour recompression, which involves capturing low-pressure waste vapour from the refining process for recompression to create pressurised steam for reuse.

Paired with renewable energy these technologies have the potential to reduce the significant contribution to overall emissions alumina production entails.

ARENA CEO Darren Miller said the study was a significant step towards making low emissions alumina and decarbonising Australian metals production.

“Meeting Australia’s emissions reduction targets will require businesses in the most energy intensive industries to incorporate renewables in their operations,” he said.

“Funding from ARENA will help South32 investigate innovative electrification options for steam generation that enable the use of renewable energy.”

South32 chief operating officer Vanessa Torres said the company had a long-term goal to achieve net zero emissions across all scopes by 2050 alongside the Federal Government’s target and to halve overall emissions from the company by 2035 from their 2021 baseline.

“Decarbonising our operations is key to achieving our goals and targets,” she said.

“The pre-feasibility study that we will undertake at Worsley Alumina, with funding support from the Australian Renewable Energy Agency, builds on the work already under way to reduce Worsley Alumina’s greenhouse gas emission.

“Electrification of the steam generation process at Worsley Alumina’s refinery has the potential to further reduce the operation’s green house gas emissions and we look forward to starting work on the project. We welcome the support from ARENA and look forward to the outcomes of the study.”