Researchers look into extracting critical metals from mine waste to boost Australia, India supply

The Olympic Dam mine in South Australia contains an inferred resource of more than 47 million tonnes of REO. (Image courtesy of BHP.).

​​New research by the University of South Australia could transform the way rare earth elements and other vital battery metals are recovered from the earth, enabling safer extraction with fewer environmental impacts.

The University’s Future Industry Institute has launched a new project that will look into new mechanisms to safely extract critical minerals from downstream ore processing, tailings reprocessing, and wastewater treatments. 

Under the lead of Dr. Richmond Asamoah, the Institute is also developing processes to safely recycle spent products from scrap batteries and magnets.

 “The process of extracting these critical materials is very damaging to the environment, with conventional mining methods generating large volumes of toxic and radioactive materials,” Asamoah said in a media statement.

“Our research will identify new technologies that have the capability to both extract minerals from existing industrial wastes and mineral tailings, and recycle and source minerals and metals from spent batteries and magnets,” Asamoah said. “As a result, we should be able to significantly reduce the amount of waste and harmful materials that can seep into the environment.”

The project will test two metal recovery techniques – resin in pulp and resin in moist mix – to extract target metals from low-grade ores, fine minerals and tailings. These processes can also be used to remove harmful substances from water and soils to minimize their environmental impact.

“We’re not only talking about environmental benefits, but also economical and sustainable technologies that countries can use to extract rare earth and battery minerals from current mining operations,” Asamoah said.

Since the initiative is funded by the Australia-India Strategic Research Fund, the researcher pointed out that India could greatly benefit from the project’s findings as it currently imports most of its rare earth needs from China, even though it hosts the world’s fifth-largest reserves of critical metals.

“This project hopes to enable Australia to export rare earth minerals to India, as an alternative to China, as well as to empower India to establish eco-technologies to extract minerals and metals within their own borders,” Asamoah said.

According to Geoscience Australia, rare earth oxides occur in the Northern Territory and all states except Tasmania. 

Data from the government agency show that Mount Weld in Western Australia is one of the world’s richest REE deposits, while other significant deposits occur in New South Wales at Toongi, in the Northern Territory at Nolans Bore and in Victoria at the Wim deposits. Olympic Dam in South Australia, however, contains an inferred resource of more than 47 million tonnes of REO, more than 23 times the total 2.3 Mt resource of Mount Weld.