Process development for recovery of chromite values from COB plant tailing samples collected from various operating plants in Sukinda

Abstract

India has reserves of chromite around 213 million tonnes located in the regions of Orissa, Bihar, Karnataka, Maharashtra and Tamil Nadu where Orissa contributed the largest share distributed in three districts mainly Jajpur, Cuttack and Keonjhar. There are 34 beneficiation plants put up in the country out of which six are captive and twenty eight are non-captive beneficiation plants. The general beneficiation process adopted by Indian Chrome ore beneficiation plant is gravity separation techniques like Floatex density separation, spiraling, hydrocycloning, tabling, etc. The plant tailings in most of COB plants in India is around 40% of ROM treated. These tailings contain lot of chromite values in fine form due to friable nature of chromite. Taking into consideration the importance of recovering valued chromite from fine tailing and their environmental impact as generation of this fines is of huge quantities generated by Indian COB plants, the Ore Dressing Division of Indian Bureau of Mines, Nagpur, conducted detailed mineralogical characterization studies on these plant tailing samples. Based on the characterization studies a beneficiation process route was evolved by deploying various equipments like conventional cyclones, stub cyclones, floatex density separator, etc. for improving the recovery of fine chromite concentrate from plant tailings of operating plants in Sukinda.