Lowering of alumina in high alumina iron ores to produce DR grade iron ore pellets

Abstract

Indian iron ores are rich in iron but contain high alumina (as high as 7%) .The alumina content in the iron ore fines used for sinter making /pellets all over the world is less than 1% , whereas iron ore fines in India assay as high as 3-5.5%.High alumina in iron ores requires high quantity of flux, resulting in a relatively larger slag volume, increase in coke consumption and a decrease in blast furnace productivity. Enormous quantity of fines generated during mechanical milling of iron ores could not be completely utilized for sinter making-hence this project was designed to develop flow sheet to produce DR grade pellets from difficult sinter feed (high alumina) iron ores of Jharkhand-Orissa region. The sample analyzing around 3% alumina had been taken for further studies to lower alumina to less than 1.5% and SiO2 less than 1% using possible state of art physical beneficiation approaches.