BENEFICIATION STUDIES ON BAUXITE MINING WASTE: A VALUE ADDITION FOR REFRACTORYINDUSTRIES

Abstract: Partially Lateritised Khondalite (PLK) rocks are the waste materials generated as a result of mining of bauxite. The major discolouring elemental impurity in the PLK is iron oxides, which render it unsuitable for its use as a refractory material. The iron can be removed by suitable beneficiation methods. The main aim of this present investigation is to prepare a value added material from the mining waste by preparation of PLK rock containing less than 2% Fe2O3 which finds application in the refractory industries and then preparation of brick suitable for industrial applications. The feed sample containing 4.31 % Fe2O3 subjected to hydrocyclone for refractory of low iron content product in the underflow. The results of these studies reveal that the hydrocyclone underflow sample contains 1.9% Fe2O3 is suitable for making bricks due to presence of low iron content. However, bricks are made from a feed sample as well as from hydrocyclone underflow and overflow products. Physical, chemical and thermo-mechanical properties of these bricks are evaluated. Mineralogical properties of these bricks are also correlated with the thermo- mechanical properties. The developed bricks are compared with the standards for their suitability in industrial applications. Hence the bauxite mining waste can be a value added material but not a waste material which at present creates environmental pollution at the mining site.