Application of magnetic separation and reverse anionic flotation to concentrate fine particles of iron ore with high sulfur content

Abstract

The sulfur content in iron ore causes technical problems in the process of sintering iron ore in steel and alloys, and environmental problems in discharging the tailing. The major challenge in the iron ore processing plant is handling the finer particles. The key objectives of this research included the concentration of Band Narges Mine iron ore (< 150 µm) as well as the reduction of the sulfur content to achieve a marketable product. First, the mineralogical characterization of iron ore was established, which showed that Fe3O4, SiO2, and CaO were the predominant minerals in the ore body. Moreover, magnetite particles with a size of < 150 µm were mainly locked into the associated gangue mineral. Second, metallurgical experiments were conducted, including magnetic separation and froth flotation. To increase the iron grade and recovery and decrease the sulfur content, two separate process flowsheets were tested, three steps of magnetic separation with a magnetic field strength of 2000 G were used in the first process flowsheets, followed by regrinding to < 74 µm and application of a three-stage reverse flotation. The overall iron grade and recovery were 76.38% and 67.9%, respectively, from this flowsheet. A five-stage successive reverse flotation followed by three stages of magnetic separation at 1000 G was carried out in the second flowsheet. The final recovery and grade of iron for this flowsheet were 77.15% and 64.3%, respectively. The ultimate content of sulfur was estimated at 0.74%.

Processing of Hematite Ore by using Magnetizing Reduction Roasting and Magnetic Separation

“…Hematite, ilmenite, and siderite are examples of weakly magnetic iron minerals that can be separated from less magnetic or non-magnetic gangue material using this technique. (11,19) high-intensity magnetic separation tests showed that ore contained mainly hematite as iron ore bearing mineral as only 30,36 % Fe corresponding to magnetite was recovered by high-intensity magnetic separation. The magnetic separation of the first group confirms it was more effective than the second group because the percentage of iron grade in the first group was increased.…”

“…The production of fine particles from excessive grinding lowers product quality and recovery while also raising processing costs. (11,12,13) The most common application of magnetic separation is to separate magnetic iron ore such as magnetite and hematite from a variety of weaker or nonmagnetic materials. Since the magnetic separation process combines the benefits of high throughput and low operating cost with being ecologically friendly, it is crucial for upgrading such low-grade iron ores.…”

Optimization of Line of Magnetite Recovery from Wet Tailings by Creating Second Medium Intensity Magnetic Field (Case Study: Processing Plant of Gol-e-Gohar Hematite)

“…Hematite is the dominant mineral containing iron in Gol-e-Gohar. Sulfur impurities in the feed, which causes environmental problems in discharging the tailing [12], are due to iron-bearing minerals such as muscovite and biotite. Nearly 67 percent of the iron ore particles in the plant are smaller than 38 microns in diameter.…”

Removing Iron Impurities from Feldspar Ore Using Dry Magnetic Separation (Part One)

“…in general, the gangue minerals in feldspar appear to have weak magnetic characteristics; just using a high-intensity magnetic separator can get a good result [23,26]. Most often, ferromagnetic materials such as magnetite are separated using dry or wet low-intensity magnetic separators, while paramagnetic minerals such as hematite are separated using high-intensity magnetic separators [27,28]. due to their low cost, high-intensity dry magnetic separators are becoming increasingly popular for the separation of paramagnetic materials [29].…”