How is iron obtained

Calcium oxide is basic as it is a metal oxide and silica is acidic as it is a non-metal oxide. Extracting iron The blast furnace Iron is extracted from iron ore in a huge container called a blast furnace. Iron ore haematite. Iron III oxide. New ore-enrichment techniques have made the use of lower-grade ore much more attractive, and there is a vast supply of that ore. Many steel plants have closed in recent decades, but this is largely because fewer are needed. The efficiency of blast furnaces alone has improved remarkably.

At the beginning of this century, the largest blast furnace in the United States produced tons of pig iron a day. It is believed that soon the possible production of a single furnace will reach 4, tons per day.

Since many of these more modern plants have been built overseas, it has actually become more economical in some cases to ship steel across the ocean than to produce it in older U. Lambert, Mark. Spotlight on Iron and Steel. Rourke Enterprises, Hartley, Edward N. Iron and Steel Works of the World.

International Publication, Lewis, W. Iron and Steel in America. Hagley Museum, Walker, R. Modern Ironmaking Methods. Gower Publication, Toggle navigation. Made How Volume 2 Iron Iron. Minerals near the surface of the earth that have the highest iron content are known as iron ores and are mined commercially. Other articles you might like:. Also read article about Iron from Wikipedia. User Contributions: 1. Very helpful article. The whole matter presented in a very precise manner. Great work.

Thank you. What is the difference between iron we use for construction and the iron we use for iron deficiency in diets? For instance, nickel increases its durability and makes it more resistant to heat and acids; manganese makes it more durable, whereas tungsten helps it maintain hardness at high temperatures, according to Jefferson Lab.

Archeologists estimate that people have been using iron for more than 5, years, according to Jefferson Lab. In fact, it turns out that some of the most ancient iron known to humans literally fell from the sky. In a study published in in the Journal of Archeological Science, researchers examined ancient Egyptian iron beads that date to around B.

Iron is mostly obtained from minerals hematite and magnetite. In smaller degrees, it can also be obtained from the minerals taconite, limonite and siderite, according to Jefferson Lab.

Iron has four different allotropic forms, which means that it has four different structural forms in which atoms bond in different patterns, according to Los Alamos National Laboratory. Those forms are called ferrites, known as alpha which is magnetic , beta, gamma and omega.

Iron is an important nutrient in our diet. Iron deficiency, the most common nutritional deficiency, can cause anemia and fatigue that affects the ability to perform physical work in adults. In a modern blast furnace, the mass of each component and the timing of its addition to the furnace are computer-controlled, responding automatically to the conditions prevailing at that time in the furnace.

The components are added in small amounts every minutes at the top of the furnace. A pressure of ca 1. Hot oxygen-enriched air is blown in near the bottom, the pipes being known as tuyeres Figure 3. Many reactions take place as the gases make their way upwards. Figure 3 A blast furnace for reducing iron ore to iron.

Temperatures vary within the furnace, the highest temperatures being at the bottom and the lowest at the top, and so the various reactions take place at different levels in the furnace.

Lower in the furnace, where it is hotter, the reduction to iron is completed. The molten iron runs down and collects in the bottom of the furnace. As it descends it absorbs carbon, phosphorus, sulfur and small amounts of other elements such as manganese and silicon from the ores, coke and limestone.

In regions of the furnace where the temperature is higher than K limestone dissociates, producing calcium oxide:. Calcium oxide, which is a base, reacts with acidic impurities in the ore, forming an aluminosilicate slag. This also absorbs much of the sulfur present in the various raw materials. The liquid slag runs to the bottom of the furnace, forming a layer on top of the molten iron.

Usually the molten iron is sent directly to the steelworks as tonne loads in refractory-lined, torpedo-shaped transfer ladles. The slag is run off, every few hours, cooled and then sent for treatment to make by-products such as cement and insulation products or to be used for road building.

The gas emerging from the top of the furnace contains nitrogen, carbon monoxide, carbon dioxide, hydrogen, water vapour and dust. After removing the dust, the gas, mixed with natural gas, is used as a fuel to heat bricks packed into 'stoves'. Figure 5 Brick stoves use the heat from the waste furnace gases to preheat the incoming air prior to it passing through the bustle pipe and the tuyeres into the blast furnace.

The heat from these stoves is used to pre-heat the air blast. These energy-saving measures have an important impact on the overall economics of blast furnace operation.