Advances in the study of high intensity conditioning as a means of improving mineral flotation performance

A systematic investigation into the hydrodynamic and chemical aspects of high intensity conditioning (HIC) prior to mineral flotation has been conducted. The objectives were to elucidate he mechanisms responsible for improvements inflotationperformance following H1C, to understand the influence of shear in the process and devise appropriate scale-up criteria. In laboratory experiments it has been shownʹ that metal flotation grade, selectivity and recovery can be improved significantly following the use of a HIC stage which, if translated to full scale operation, could give excellent improvements in process economics. One of the mineral flotation processes selected for study was nickel rougher flotation from a nickel sine orebody, obtained from a currently-operating Western Australian mineral processing site. Extensive experimental work using rigorously designed laboratory procedures has been completed to study changes to impeller design and investigate pulp rheology with the aim of developing scale-up procedures. Such parameters as total work input, rate of work addition, impeller dimensions and configuration, point of addition of reagents and effect of temperature have been studied in detail. The construction of a novel, high-shear, continuous HIC cell system has also taken place to optimise shear efficiency. Generic conclusions have been drawn regarding scale-up of cell design and principles of HIC cell operating procedure.