Investigation of sulfur removal from Soork iron ore

The present work aims to study the feasibility of sulfur removal from Soork iron ore down to lower than 0.1% using the flotation process. According to the characterization analysis, the ore consists of 50.37% iron and 4.12% Sulfur. The ore sample was divided into different size classes using screen size analyzing method. Then, wet magnetic separation experiments were conducted for three size classes in order to determine the degree of liberation. The d80=106 µm size class was found as an appropriate degree of liberation. Wet magnetic separation experiments were performed at 800G intensity for 3 min feeding and water flowrate of 4 liters per min, drum rotational speed of 54 RPM with rotation parallel to the direction of feeding in which an iron grade of 63% along with a Sulfur content of 0.52% with an iron recovery of 96% was obtained. To do further Sulfur reduction, the concentrate of the magnetic separation was reprocessed using reverse flotation to remove pyrite. Then, to reach an optimum operational condition in terms of flotation time and reagent usage, a few tests were performed and finally the flotation time of 5 min along with a collector dosage of 100 g/Mg in pH=9 was found to be the best possible condition to reach a Sulfur content of lower than 0.1%. Also, a yield recovery of 95.96% for iron concentrate with an overall iron recovery of 94.9% was obtained.