Laboratory-based flowsheet development of Iranian ilmenite upgrading

A process root selection was investigated on hard rock titanium deposit of Qaraaghaj, Ueromieh, Iran. The deposit contained ilmenite as valuable mineral with average grade of 8.5% TiO2. Mineralogical studies performed by optical microscopy, SEM and XRD, indicated that the ore consists mainly of ilmenite, magnetite, titanomagnetite and some gangue minerals such as pyroxene, olivine and plagioclase. The ilmenite was ainly granules form but some lamellae forms of ilmenite were found inside the magnetite. Also very narrow lamellae of hematite and hemo-ilmenite were found inside the ilmenite. The liberation degree of ilmenite was determined 150 microns. Several concentrating circuits were investigated for selection of an optimum ilmenite upgrading flowsheet. Among them, the combination of heavy liquid (Clerici solution with SG=4) and low intensity-wet magnetic separator (LIWMS) presented an ilmenite concentrate containing 43.5% TiO2. An ilmenite concentrate grading 45% TiO2 was obtained by the combination of shaking table and LIWMS. A modification on latter flowsheet consisting of regrinding of LIWMS tailing and recirculating it on LIWMS a final concentrate could be obtained with 44.5% total recovery.