BHP and Rio Tinto have collaborated to expedite technology development that might dramatically boost water recovery from mine tailings, reducing possible safety hazards and environmental footprints associated with tailings storage facilities.
In a statement, Rio Tinto said the first project would include putting an innovative large-volume filter unit to the test at a BHP copper mine in Chile, where it will extract up to 80 per cent of the water in the tailings stream before being deposited in a storage facility.
Rio Tinto will provide its experience from implementing smaller-scale bauxite tailings filters at alumina refineries since 2005. Both organisations will collaborate with premier technology and equipment providers, technical specialists, research organisations, and academic institutions.
The filter unit is already being manufactured. The pilot construction begins in early 2023, with operations starting in early 2024. The pilot will assess the scalability and cost-effectiveness of a large-scale tailings filter unit in worldwide mining operations.
Extracting more water from tailings would lower possible problems associated with moisture in storage facilities, reduce the footprint of such facilities, and enable chances to productively reuse tailings, such as raw material for the glass, construction, or agriculture industries.
The extra water collected from tailings through filtering could be reused in processing plants, lowering overall water use.
“The world will need more critical minerals in the decades to come to support economic development and decarbonisation pathways. It is important that we keep working together across the global mining sector to raise standards and make sure our operations are safe and sustainable as they can be. Responsible management of tailings and improved water use is a big part of that,” BHP Chief Technical Officer Laura Tyler said.
Rio Tinto Chief Technical Officer, Mark Davies, stated: “It is in everyone’s interest that we, as an industry, find safer and more sustainable ways to manage tailings. As two of the leading companies in the sector, we want to bring our combined knowledge and expertise to address this challenge.”
Tailings are typically a liquid slurry composed of fine metal or mineral particles and water produced when mined ore is crushed and finely processed in a milling process for the metals and minerals of interest to be recovered.
