‘High voltage’ mineral processing technology with the potential to significantly reduce energy consumption and help the mining industry decarbonise is one step closer thanks to funding from the Resources Technology and Critical Minerals Trailblazer.
With support from the Trailblazer and industry partners, researchers from the Sustainable Minerals Institute’s (SMI) Julius Kruttschnitt Mineral Research Centre (JKMRC) are commercialising High Voltage Pulse (HVP) technology, which uses a short-pulsed high voltage discharge, akin to a lightning strike, to selectively break mineralised ores whilst keeping barren rocks intact.
This selectivity makes it possible to choose the material which should go to the processing plant and leave behind material which contains little or no metal.
Reducing energy consumption at processing plants
JKMRC Senior Research Fellow and HVP project leader Dr Christian Antonio said the technology offers industry a meaningful step towards decarbonisation.
“Mineral processing is the most energy intensive part of the mining value chain and is a significant consumer of energy globally,” Dr Antonio said.
“By applying HVP before conventional processing begins, you can reduce the energy required to process that material at later stages.
“These savings come by separating ‘barren’ rock from the valuable mineralised rocks, which prevents energy being wasted on it, and weakening the material that is left behind so it is easier to process.
“Our research indicates that this leads to a notable decrease in processing time and energy consumption, with grinding alone seeing a reduction of approximately 30%.
“The combined advantages contribute to a more efficient process, a reduced process footprint, and ultimately, a significant decrease in energy usage.
How High Voltage Pulse technology works
Research into HVP technology at the JKMRC started under Emeritus Professor Fengnian “Frank” Shi in 2007.
“As Frank famously claimed, ‘If you are in a thunderstorm with someone that is holding a metallic umbrella, it is much more likely that the lightning will strike them than you’,” Dr Antonio said.
“This same concept is at work with HVP technology – electrical energy automatically targets the conductive mineral particles within a rock and breaks the rock up as it makes its way to them.
“To deliver this energy we have electrified a conventional piece of mineral processing equipment that sorts rocks by size, meaning we are both zapping the rocks and sorting the fragments simultaneously.
“We see this as a more efficient way to deliver the energy while achieving the over one hundred tonne per hour throughputs required by the mining industry.
“During the process you can visibly see lightning arcs targeting mineralised rocks."
Industry interest
Several mining industry partners are supporting the Trailblazer project, including Newmont and JKTech.
HVP Technology is now one of the main focuses of the JKMRC’s Separation Group.
Group Leader Associate Professor Kym Runge said there is wide industry interest in the technology.
“They are very interested in the role HVP technology could play in decarbonising operations, and a key part of this project is showing our partners that the technology can feasibly be added to their plants,” Associate Professor Runge said.
“We will build a business case for HVP usage that will quantify its benefits, then we will design a HVP unit integrating our technology and progress that to commercialisation.
“Ultimately the plan is to build a pilot plant and demonstrate the benefits of HVP at one of our sponsor’s sites.”
