Recovery of Iron Values from Discarded Iron Ore Slimes

  • Singh Rahulkumar Sunil
  • Veeranjaneyulu Rayapudi
  • Nikhil DhawanEmail author


The ever-increasing demand for steel and the subsequent depletion of high-grade ores requires the massive utilization of low-grade iron ores. In the present study, an iron ore slime sample containing 56.1% Fe was investigated using physical beneficiation, carbothermal reduction, and a microwave-assisted process; however, physical beneficiation and microwave exposure were found to be inefficient as they yielded lower iron recovery. Using coconut shell as an alternative reductant was found to be promising and does not lead to the formation of higher iron oxides, such as fayalite and wustite phases. The microwave-assisted carbothermal reduction was found at par with conventional reduction, saving time and heating. The optimum magnetic concentrate obtained in both carbothermal reduction routes (microwave and muffle furnace: Fe grade, Fe recovery, and yield of 64.3, 97, and 84%, and 67, 99, and 83%, respectively) are suitable for alternative iron-making or blast furnace units.


Iron ore slimes Magnetic separation Carbothermal reduction Microwave Recovery 



The authors would like to thank and acknowledge the funding agency Science Engineering Research Board (SERB) for providing early career research (ECR) funds.

Compliance with Ethical Standards

Conflict of Interest

On behalf of all authors, the corresponding author states that there is no conflict of interest.


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Copyright information

© Society for Mining, Metallurgy & Exploration Inc. 2019

Authors and Affiliations

  • Singh Rahulkumar Sunil
    • 1
  • Veeranjaneyulu Rayapudi
    • 1
  • Nikhil Dhawan
    • 1
    Email author
  1. 1.Metallurgical and Materials Engineering DepartmentIIT RoorkeeUttarakhandIndia

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