GRINDING: Novel HVP pre-concentration could change everything

AUSTRALIA – The Coalition for Energy Efficient Comminution has awarded its 2017 CEEC Medal to the SMI-JKMRC of the University of Queensland for a process that has the potential to significantly reduce grinding energy requirements, thus decrease mineral processing costs. [caption id="attachment_1003723422" align="alignright" width="300"] Frank Shi in front of the selFrag Lab equipment. (Image: CEEC)[/caption] JKMRC has created a pre-concentration technique that uses high voltage pulses (HVP) to split ore particles by grade. HVP was tested in pre-concentration in the 1970s when it was used to break ore particles to about 100 microns. The process was energy intensive, making it too expensive for industrial application. Rather than break all ore particles, the new HVP technique uses much less energy by selectively breaking mineralized particles but not particles of gangue. After HVP processing, ore particles can be screened to produce low and high grade ore streams. JKMRC researcher professor Frank Shi said electrically induced breakage offered a new application of HVP in the mining industry. “We recognized that a shorter burst of electrical energy was able to successfully break rocks selectively through the more conductive minerals and that this could help fast track separation of the valuable minerals from gangue minerals in a number of ore types. The process also has the potential for better mineral liberation and particle pre-weakening in the HVP treated product,” he said. Frank said the new applications of HVP gathered momentum in 2007 via an ARC-funded, AMIRA-managed project. The JKMRC led the project in collaboration with a number of Australian universities. See what else the CEEC is doing to bring grinding into the future at www.CEECtheFuture.org.