Selective Dispersion of Rejected Iron Ore Ultra Fines for Feed to Blast Furnace and Minimize Environmental Issues

Indian iron mines dumps huge quantity of ultra fines containing high gangue minerals resulting in loss of iron values and environmental issues. The major gangue minerals containing alumina, silica and phosphorous are the cause for contamination of Indian iron ore. It has, therefore, become an urgent need to utilize these off-grade ultra fines after making it suitable for blast furnace charging. Due to the fine nature of these ultra fines, selective dispersion studies have been thought of. Two types of dispersants (i) inorganic, sodium hexametaphosphate and (ii) organic, sodium salt of poly acrylic acid have been tried. The performance of these two types of dispersions has been evaluated in separation process. Sodium salts of poly acrylic acid shows better separation of alumino silicate minerals in the ultra fines whereas, sodium hexametaphosphate efficiently separates out silica from the iron bearing minerals.