Utilization of Iron Ore Slimes: A Future Prospective

Abstract

In India, iron ores processing industries play a vital role in the Indian economy. During the washing and processing of iron ores, slimes less than 0.15 mm are generated and discarded into the tailing pond. These slimes need processing as they cannot be used directly in blast furnaces. In the present investigation, a typical iron ore slime sample containing 59.22% Fe, 4.76% SiO₂, and 4.57% Al₂O₃ was taken. The desliming operation was carried out by using 2” Mozley hydrocyclone. The process variables used to attain the optimum condition of desliming include the spigot opening, the feed pressure, and the diameter of the vortex finder maintaining the pulp density at 10% solid. The deslimed sample was treated by different techniques including an enhanced gravity separator to achieve iron concentrate with 65% Fe so that it can be used for steel making through pelletization. The yield of the magnetic concentrate is about 46.8% with 65% Fe. To improve the yield, the overflow from 2” hydrocyclone and the rejects from magnetic separation were deslimed and processed to recover the iron values. The final concentrate is 74% yield with 64.8% Fe, 1.76% SiO₂, and 1.8% Al₂O_3.

Keywords:

• desliming
• enhanced gravity separator
• hydrocycloning
• iron ore slimes
• reverse flotation

ACKNOWLEDGEMENTS

The authors would like to thank the Director, National Metallurgical Laboratory, Jamshedpur for his valuable guidance and kind permission for publishing this work. This investigation was supported by CSIR Network project NWP-0031.

Notes

WRO: with respect to original feed.

WRO: with respect to original feed.