A sustainable solution for mine waste is imminent

mine waste

Revegetation underway at a red mud site near Gladstone. Image: UQ.

Researchers at The University of Queensland’s Sustainable Minerals Institute (SMI), Rio Tinto and Queensland Alumina Limited (QAL) have developed a bio-engineering technology that could rehabilitate mine waste back to useful soil. 

The process will transform the bauxite residue known as “red mud” into a soil-like material capable of hosting plant life. 

“The team has secured more than $3 million in funding from Rio Tinto and QAL that will allow us to trial the technology at an operational scale at two red mud sites,” SMI professor Longbin Huang said. 

“This project demonstrates how transformative industry-academia partnerships can be – Rio Tinto and QAL have supported the research for the past eight years, from proof of concept to full field trials.” 

There are more than four billion tonnes of red mud stored in dams around the world, with Australia the second largest producer of the mineral waste by-product of alumina refining. 

mine waste
Professor Longbin Huang and his research group. Image: UQ.

 “The salinity and alkalinity associated with the minerals in red mud means rehabilitation can be challenging,” Huang said. 

“The process we have developed is game changing, as it involves eco-engineering the mineral and organic constituents of the red mud into material that is more hospitable to plant life.” 

Compared with traditional methods, this is a more sustainable and cost-effective way of managing red mud. Traditionally, companies would excavate and transport metres of topsoil from other locations to cover hectares of waste. 

The QAL team is excited to see the project moving to a full-scale trial. 

“After years of watching various trials unfold within our daily work environment, to now be able to see the tangible outcomes of UQ’s work has been encouraging,” QAL Environment and Tailings manager Trent Scherer said. 

“QAL is committed to minimising our environmental footprint through our $440 million 5-Year Environmental Strategy, and the funding and resources provided to this project are further steps in that journey.”