Mineral processing of heavy mineral sands from Malawi and Malaysia

Processing of heavy mineral sands involves many techniques including gravity, magnetic and electrostatic separation. As part of a laboratory programme to develop effective mineral processing techniques, two mineral sands from Malawi and Malaysia were processed using the standard techniques, with emphasis placed on the Carpco electrostatic separator. These sands were initially characterised mineralogically by scanning electron microscopy (SEM), electron microprobe analysis (EPMA) and X-ray diffraction (XRD). The same techniques were also used at a later stage to characterize the mineral concentrates. Mineral processing involved screening (to size the sands), gravity separation (to remove the less dense, or 'light', minerals), and magnetic and electrostatic separation (to produce concentrates of ilmenite, zircon, rutile and monazite).