Enhanced recovery of zircon using a REFLUX™ classifier with an inclined channel spacing of 3 mm

Abstract A REFLUX™ Classifier (RC™), consisting of a fluidized bed with a system of inclined channels above, was used to recover zircon from an ultrafine, low grade mineral sands feed, deslimed to varying degrees below 38 μm. This paper builds upon previous studies concerned with mineral sands, revealing here the benefits of using an inclined channel spacing of 3 mm. The solids feed flux was increased from 22.5 through to over 40 t/(m2 h), resulting in the zircon recovery decreasing only marginally from approximately 99% to 97%, with a concentration upgrade of approximately 13. The partitioning of the silica sand and the zircon to the underflow were found to be reasonably consistent with the recently determined partition surface for the REFLUX™ Classifier based on a 3 mm inclined channel spacing. The zircon recovery at the ultrafine sizes was higher than expected, a result attributed to the favourable hindered settling of the zircon within a suspension dominated by silica sand.