- Titanium-magnetite
- Apatite-magnetite
- Magnetite
- Magnetite-hematite
- Goethite-hydrogoethite
Iron ores are rocks from which metallic iron can be economically extracted. These rocks are usually found in the form of hematite (Fe2O3) or magnetite (Fe3O4).The color of iron or can be different and depends on the place of its field. Iron ore is the main material to produce pig iron – raw material, which is used to make steels. Frankly speaking, iron ore plays nearly the main role in economics, excluding oil.
It is hard to imagine the contemporary life without steel from which many things around us are made. The basis of this metal is iron produced upon ore smelting. Iron ore types are different in origin, quality, mining method, in its mineral composition, the percentage of metals and impurities, as well as the usefulness of the additives themselves. All mentioned determines the reasonability of its extraction.
Today, the following types of raw materials are extracted for further metal smelting:
Iron ore is considered rich when contains at least 57% of iron. Nevertheless, mining can be deemed purposeful at 26% of iron. Iron in the rock composition is often found in the form of oxides, the remaining additives are silica, sulfur and phosphorus.
How is iron ore mined?
Banks of iron ore are occurred at different depths ant that conditions the methods of its extraction from the Earth’s interior.
Open-pit method. All-around method of quarrying is used when deposits are located at the depth of 200-300 meters. Field development is performed with powerful excavators and rock fragmenting installations. Then materials are transported to a mining and processing complex.
Mining. The mining method is applied for deeper ore beddings (600-900 meters). First, the mine shaft with drifts are developed and then fragmented rocks are transported by conveyors to the surface and sent to processing plants.
Hydraulic mining. This method is supposed a well drilled down to a rock formation. At the next stage water at high pressure breaks rocks and ore is extracted. But this method is used quite rarely. For example, only 3% of raw materials is produced by hydraulic mining, and by mining method - 70% of that.
Examples of iron ore applications
Steel is an alloy of iron and carbon. Carbon functions as a strength-producing material. Typically, such an alloy contains from 0,1 to 2,14% carbon, and steel is deemed high-carbon when carbon rate exceeds 0,6%.
At present, steel plays significant role in production of a wide range of goods, equipment and machines. This metal is characterized by high strength parameters and excellent flexibility, ductility, and other technical, physical and chemical properties. Alloying additives enhance metal strength and wear resistance.
Cast iron is the second material produced from iron ore. It is also an alloy of iron and carbon; the latter contains more than 2.14%. Cast iron is used in many industries, but especially in mechanical engineering. This metal is also used in steel manufacturing (open-hearth furnaces and Bessemer process).