Detrital iron ore deposits are found downhill of the BIF enrichment deposits from which they have been eroded. Further resource and production information.
As with most iron ore mines throughout the world, all the major Australian iron ore mines are open cut. The iron-ore bearing rock is first blasted and dug up from open pit mines. The ores from the major mines in Western Australia's Pilbara region are hauled from working faces to crushing and screening plants using trucks that can carry over tonnes.
Hematite and magnetite ore processing includes crushing, screening and grinding to produce hematite lumps and fines. Magnetite ore is further processed through magnetic separation, an important process in producing magnetite iron concentrate. Concentration includes all the processes that will increase upgrade the iron content of an ore by removing impurities.
Beneficiation, a slightly broader term, includes these processes as well as those that make an ore more usable by improving its physical properties e. Many of the iron ore mines employ some form of beneficiation to improve the grade and properties of their products. At many operating mines, including Mount Tom Price, Paraburdoo, Mount Whaleback and Christmas Creek, ore processing facilities have been constructed to enable beneficiation of low-grade iron ores, including ores which have been contaminated with shale, to be mined and, after upgrading, sold as high-grade products.
Pelletising is a treatment process used for very fine or powdery ores. Pellets are an ideal blast furnace feed because they are hard and of regular size and shape. In Australia, concentrates pumped from Savage River are pelletised at Port Latta for shipment to domestic and overseas markets and fine Middleback Range ores are pelletised prior to smelting in the Whyalla blast furnace.
Sintering is a process used to agglomerate iron ore fines in preparation for blast-furnace smelting and is usually carried out at iron and steelmaking centres. It involves the incorporation of crushed limestone, coke and other additives available from iron and steelmaking operations.
These additives include wastes extracted from furnace exhaust gases, scale produced during rolling mill operations and coke fines produced during coke screening. White-hot steel pouring out of an electric arc furnace. Pig iron is an intermediate step in the production of steel and is produced by smelting iron ore commonly in lump, pellet or sinter form in blast furnaces.
Blast furnaces in Australia are located at Port Kembla and Whyalla. The removal, by oxidation, of impurities in pig iron such as silicon, phosphorus and sulfur and the reduction in the carbon content, results in the production of steel. Adding metals like nickel, chromium, manganese or titanium gives steel special properties like electrical resistance and resistance to wear, rust, impact, shock or expansion when heated.
The cooled steel is shaped and can be coated with tin, zinc or paint to help protect it from rusting, creating products such as Zincalume and Colorbond. The Age of Iron , Chapter 5. Tewari, Rakesh Hematite and hematite powder on streak plate.
Source: Geoscience Australia. Coolac meteorite - iron meteorite. Australia's major iron deposits and mines Pure iron is needed for proper plant growth. Breaking down the ore from its impurities is more difficult. This is achieved through a processed called smelting. Smelting involves heating up the ore until the metal becomes spongy and the chemical compounds in the ore begin to break down. This process releases oxygen from the ore, one of the most common impurities in the metal.
The facility used to smelt the iron is referred to as a bloomer. There, a blacksmith burns charcoal with iron ore and a good supply of oxygen. The carbon in the charcoal combines with the oxygen to create carbon dioxide and carbon monoxide.
These gases are carried away, leaving behind the heavier elements. The metal never gets hot enough to melt completely, just hot enough to become a spongy mass containing iron and silicates. Heating and hammering this mass forces impurities out and mixes the glassy silicates into the iron metal to create wrought iron. Park Passes. Technical Announcements. Employees in the News. Emergency Management. Survey Manual. Iron ore is a mineral substance which, when heated in the presence of a reductant, will yield metallic iron Fe.
It almost always consists of iron oxides, the primary forms of which are magnetite Fe 3 O 4 and hematite Fe 2 O 3.
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