Processing of low grade graphite ores of orissa, India

Low grade graphite samples containing 12.2–13.1 % fixed carbon from Rajunagfena, Orissa, India have been investigated for characterisation and amenability to beneficiation. The graphite is of the well crystallised flaky variety, and is associated with orthoclase, quartz, plagioclase, biotite, garnet, sillimanite, kaolinite as dominant gangue minerals. The textures, microstructures and liberation of graphite and their implications in beneficiation are described in this paper. The optimum liberation size of the graphite was determined to be below 210 μm Beneficiation studies indicated that a concentrate with 79% fixed carbon, at a recovery 80.1% can be achieved by cleaning the rougher concentrate five times in a conventional flotation cell. Almost similar grade and recovery can be obtained in two stages by column flotation.