Magnetic iron ore

This mineral is an important ore of iron, 72 -r heing metallic iron. Magnetite sometimes is referred to as magnetic iron ore. 

Magnetite Magnetic iron ore FejO, FeO-Fe Oj A spinel Black Metallic to dull 72,4 An important ore of iron, e.g. in the big deposit at Kiruna in the far north of Sweden... 

In magnetic iron ore, magnetite, the V-content can be 1-2%. This is the case in South Africa. The Bushveld-complex in Transvaal is a very large magmatic magnetite formation. In the eastern and western parts of this complex, there are heavy deposits of titaniferous rock with a vanadium content of up to 2%. That is one of the biggest vanadium reserves of the world. China is, however, reported to have the greatest reserves. The uses estimates that the world vanadium reserve base is sufficient to meet vanadium demand for many hundreds of years. 

Rutile (Ti02) and ilmenite (FeO Ti02) are used as the ores of titanium. The ilmenite is required to remove iron since it is a solid solution of magnetic iron ore and titanium oxide. There are two processes in the refining process to remove iron from the ilmenite. 

Pure iron is a silvery white, relatively soft metal and is rarely used commercially. Typical properties are Hsted in Table 1. Electrolytic (99.9% pure) iron is used for magnetic cores (2) (see Magnetic materials, bulk). Native metallic iron is rarely found in nature because iron which commonly exhibits valences of +2 and +3 combines readily with oxygen and sulfur. Iron oxides are the most prevalent form of iron (see Iron compounds). Generally, these iron oxides (iron ores) are reduced to iron and melted in a blast furnace. The hot metal (pig iron) from the blast furnace is refined in steelmaking furnaces to make steel... 

Low intensity magnetic separators are used to upgrade iron ores containing magnetite. Dry separators are used for coarse (up to 100 mm in size) ore and wet separators are used for fine (—9.5 mm) ores. 

High intensity magnetic separators are used to upgrade iron ores containing hematite or ilmenite. Dry separators require ore that is finely sized and bone dry. They are dusty, expensive, and have a low capacity. Wet separators have larger capacity, are less dusty and can handle ore sizes up to 1 mm. 

SL/RN Process. In the SL/RN process (Fig. 4), sized iron ore, coal, and dolomite are fed to the rotary kiln wherein the coal is gasified and the iron ore is reduced. The endothermic heat of reduction and the sensible energy that is required to heat the reactants is provided by combustion of volatiles and carbon monoxide leaving the bed with air introduced into the free space above the bed. The temperature profile in the kiln is controlled by radial air ports in the preheat zone and axial air ports in the reduction zone. Part of the coal is injected through the centerline of the kiln at the discharge end. The hot reduced iron and char is discharged into an indirect rotary dmm cooler. The cooled product is screened and magnetically separated to remove char and ash. 

Solenoid magnetic separators are designed for batch-type, cyclic, and continuous operation. Devices which can use matrices of expanded metal, grooved plates, steel balls, or filamentaiy metals have been designed. Continuous separators with capacities to 600 t/h for iron ores (similar to the Brazilian hematite) are commercially available (Sala International Inc.). Selection of the method of operation is apphcation-dependent, being based on variables such as temperature, pressure, volume of magnetics in the feed, etc. 

Marston Sala high-gradient magnetic separator Electromagnet, SI 1 percondi icting 20,000 50,000 Steel wool, expanded metal, steel halls 25x Itf Strongly to very weakly 0.0001-2 Iron ores, industrial minerals, coal, liquefied coal, wastewaters, purifiers, catalyst recovery, chemical industry... 

Name from magnes (Latin = magnet) manganese dioxide (Mn02) was for a long time thought to be some type of iron ore... 

NISCO (National Iranian Steel Corporation), 1980. Report on result of search and evaluation works at magnetic anomalies of the Bafq iron ore region during 1976-1979. Unpublished internal report, 260 p. 

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