Recovering minerals from mining waste

The University of Newcastle has received $1 million in funding to test technology that will boost efficiency across the minerals processing industry by reducing the amount of valuable resources currently being lost in extraction processes. The university was one of nine grant recipients announced under the Global Innovation Linkages program.

“Following mining, valuable minerals are mixed up with low-value minerals that need to be separated, via either a gravity or flotation process,” explained Laureate Professor Kevin Galvin (pictured). Without recovery, these mineral particles would otherwise be sent to tailing dams.

Working with Dr Jamie Dickinson, Professor Galvin developed the Reflux Flotation Cell (RFC), which is designed to recover mineral particles from mining waste streams. The device is said to process materials five to 10 times quicker than current technologies, providing the industry with an economically viable solution to separate fine coal from tailings waste, for example.

“One of our units about 2 m in diameter would process the equivalent of 15 domestic swimming pools per hour (1000 m³/h), extracting the desired materials,” said Professor Galvin. “Conventional systems would require up to 10 of these units to manage the same volumetric flowrate. The RFC also generates a much cleaner product. This additional product is then dewatered and combined with the other product from the plant.”

Two full-scale RFC units will be installed at a Hunter Valley mine site this year, following six years of fundamental research and pilot trials carried out by the University of Newcastle researchers and industry partners. Professor Galvin’s related technology, the Reflux Classifier, has already been deployed worldwide.