Beneficiation of low grade Kyanite from Magarmohan Kyanite Mines, Pallahara, Orissa

Abstract

A sample of low grade Kyanite from Magarmohan Kyanite Mines, Pallahara, Orissa, was received from Messrs. S.Lal and Co. Private Ltd., for beneficiation studies. The sample as received assayed 51.6% Al2O3, 41.2% SiO2, 1.1% Fe2O3, 1.4% CaO, 0.41% MgO, 1.8% K2O+Na2O and 1.7% L.O.I. Hydro- classification followed by tabling at-48 and -65 mesh sizes did not give satisfactory results. Flotation of a deslimed feed at 4.9 pH employing lactic acid and sodium sulphonate followed by one cleaning using lactic acid yielded the best concentrate assaying 60.7% Al2O3 and 1.07% Fe2O3 with a recovery of 67.4% Al2O3.In another test, mica was first Aeromine 3037 and fuel oil followed by Kyanite concentrate assayed 58.8% Al2O3 with a recovery of 70.7% Al2O3. Another flotation test employing sodium silicate, sodium hydroxide and oleic acid emulsion followed by two cleanings of the rougher float, using sodium silicate each time, yielded a concentrate assaying 60.0% Al2O3 with a recovery of 57.0% Al2O3.