They are then used to help heat the air blast, required if blast furnace is to reach the high temperatures needed to produce molten iron. With modern blast furnace ironmaking an introduction the reader has a compact compendium of the blast furnace process available. The blast furnace is designed to reduce iron oxides and to separate the resulting iron from the large quantities of impurities in the ore. Once a blast furnace is started it will continuously run for four to ten years with only short stops to perform planned maintenance. The structure of pig iron blast furnace is made of steel plate and refractory bricks,and its shape is vertical drum like bowling pin.
A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals, generally pig iron, but also others such as lead or copper. Operational results proved stable operations with a lump ore fraction up to 80%. It is widely distributed, combined with oxygen as iron oxides. Minerals and ironmaking reactions in blast furnaces. Molten iron ore is tapped at the bottom of the blast furnace, poured into the iron ladle and removed for use. For the hotter metals like nibral at 2300f to iron at 3000f must use a clay or silicon carbide crucible. With design, manufacture and installation of pig iron, ferromanganese smelting blast furnace, sinter plant, hot air stove, cip system, shaft furnace, lime kiln, etc. Kinetics and modeling of iron making blast furnace overview the iron making blast furnace is a complex multiphase flow reactor. The production of iron in a blast furnace is an important industrial process, although other methods for iron production are also in use. Blast furnace smelting equipment sinter plant lime kiln.
The pig iron blast furnace provides the means by which iron is rapidly and efficiently reduced from iron ore and it is the basis for all primary steelmaking. Use of pure oxygen while blast furnace operators aim to enrich the hot blast. In the furnace, hot metal along with slag is processed from the raw material which gets collected in the hearth and blast furnace gases come out of blast furnace from the top. The melt was carburized and the manufactured iron ceased to be malleable.
To develop computational and mathematical abilities to be applied for process design and control. The iron that comes out of the blast furnace if allowed to cool is called cast iron or pig iron it is very impure containing about 4% carbon. The blast furnace cannot operate without coke, but since it is the most expensive feed material used in the blast furnace iron making process, there has always been a demand to minimize its use. This book focuses on the control of the blast furnace process with respect to thermal control, gas flow control and casthouse operation. The most common ore of iron is called haematite iron iii oxide. The formation of iron and steel the blast furnace 2. Ironmaking 101 from ore to iron with blast furnaces. Blast furnace iron making is the main method for modern steel production,the process of blast furnace is an important part. For the hotter metals like nibral at 2300f to iron at 3000f must use a. An interesting representative of such processes is the blast furnace ironmaking process 1 2 3, which uses multisensors such as two manual measurements and two infrared acquisitions to. A jet of air is used to burn the carbon to form the gas carbon dioxide. The basic idea involves the heating of an iron oxide, often haematite, fe 2 o 3, with carbon.
Recent developments in blast furnace ironmaking technology. Coke is the most important raw material fed into the blast furnace in terms of its effect on blast furnace operation and hot metal. The blast furnace is a fundamentally vertical shaft varying in height from 24 to 33 meters with the diameter at the hearth of about 8. Blast furnace fans are essential to drive heated air into the furnace and our id fans are then used to draw the furnace gases. Mini blast furnace mbf is the most proven technology, as revealed by one recent global iron production data. The authors have very extensive experience as operators as well as consultants to many steel plants worldwide. An interesting representative of such processes is the blast furnace iron making process 1 2 3, which uses multisensors such as two manual measurements and two infrared acquisitions to. A potent symbol of a steelworks, blast furnace is a facility to produce hot metal by smelting iron ore. Iron making deals with the extraction of iron from ores because iron without processing is only available in meteorites.
Ironmaking and steelmaking metallurgical and materials. Creating steel from lowgrade iron ore requires a long process of mining, crushing. Iron oxides can come to the blast furnace plant in the form of raw ore, pellets or sinter. Steel making converts molten iron into steel which is much more useful. Installation of big blast furnaces not only requires huge capital but the.
The haematite reacts with carbon in the cast iron to give pure iron and carbon monoxide gas which escapes. The nonuniform flow, heat transfer, and carbon dissolution from the refractory and the coke bed dead man cause large differences in thermal conditions and hot metal composition. The iron ore concentrate is now mixed and ready for the pelletizing process. Please practice handwashing and social distancing, and check out our resources for adapting to these times. This furnace will be the indias largest blast furnace to date. Coke iron was initially only used for foundry work, making pots and other cast iron goods. The blast furnace cannot operate without coke, but since it is the most expensive feed material used in the blast furnace ironmaking process, there has always been a demand to minimize its use. Valia, scientist, ispat inland inc introduction a world class blast furnace operation demands the highest quality of raw materials, operation, and operators. All the three ingredients are crushed into small round pieces and mixed and put on a hopper which controls the input. Finally i needed a furnace that could reach 3000f so i could pour brass and iron. Wrought iron is the purest form of iron available commercially available and is prepared from cast iron by heating cast iron in a furnace lined with haematite fe2o3.
Electric furnaces for making iron and steel page 63 unt. This section deals with the types of iron and steel which are produced as a result of the steel making process. The majority of pig iron produced by blast furnaces undergoes further processing to reduce the carbon content and produce various grades of steel used. This section deals with the types of iron and steel which are produced as a result of the steelmaking process. Introduction kobe steel started operation as an integrated steel manufacturing company with the blowingin of the no. While gasbased as well as coalbased dri production routes produced 2. It is suitable for students of metallurgy as well as. Aug 03, 2011 the calcium silicate melts and runs down through the furnace to form a layer on top of the molten iron. The process injects oxygen through the molten iron removing most of the. Iron very rarely occurs in the earths surface as a metal.
Molten iron ore is tapped at the bottom of the blast furnace, poured into the iron ladle and. This furnace is designed for a twenty year campaign. Today the strategy of the ironmakers is to extend the campaign life of blast furnace as much as possible so that the total relining is required at least after 14 15 yrs of operation. Blasts furnaces are used for smelting during the production of metals such as iron, lead, zinc, and copper. This project has been performed to increase the steel making production capacity of esfahan steel company in iran from 2.
Extraction of iron in a blast furnace reduction haematite o. The pig iron produced by the blast furnace has a relatively high carbon content of around 45%, making it very brittle, and of little commercial use. It is suitable for students of metallurgy as well as for blast furnace operators and management. Although there are various iron making processes, the mini blast furnace route is the most preferred in the modern day scenario. The limitation on the recycle of steelmaking slag to the iron blast furnace is typically the impurity content, particularly the sulfur, phosphorus, and zinc. In the furnace, coke supplies heat energy while physically maintaining the permeability of the blast furnace bed. Iron making solutions to extend blast furnace lifetime. Danieli corus has enjoyed an incredible journey with indian steel industry over the years.
Pdf technological changes in blast furnace iron making. The calcium silicate melts and runs down through the furnace to form a layer on top of the molten iron. Foundry work was a minor branch of the industry, but darbys son built a new furnace at nearby horsehay, and began to supply the owners of finery forges with coke pig iron for the production of bar iron. Step 2 the blast furnace the outer case is a water cooled steel casing that provides the main support for the 30 m high furnace. If all the carbon is removed from the iron to give high purity iron, it is known as wrought iron. Pdf technological changes in blast furnace iron making in. Blast furnaces are also called high ovens a blast furnace is usually built with a steel case and bricks made of magnesia inside the case. Snclavalin specializes in epcm for all phases of the iron and steel making processes including providing services for coke plants, blast furnaces, casters, industrial furnaces, rolling mills, finishing and coating lines, air pollution control, water pollution control, chemical processing, and bulk material handling systems. In fact it is believed that iron makes up about 5% by weight of the earths crust. The second most important after blast furnace gas source of carbon monoxide at iron and steel companies is converter gas 32. Ironmaking plant is an integral part of any steelworks which. Thereby iron production is divided into two stages.
Pelletizing a pellet plant contains a series of balling drums where the iron ore concentrate is formed into soft pellets, in much the same manner that one rolls a snowball, to make a pellet about the size of a marble between 14 and 12. Iron is made by reacting iron ore iron oxide and impurities, coke a reductant and limestone caco 3 in a blast furnace iron ores with lower iron content such as taconite are first processed to concentrate the iron level and drive off volatile impurities. The rated capacity of this furnace is 9,500 tons of hot metal per day with pulverized coal injection system of 200 kgthm. Iron ore processing for the blast furnace courtesy of the national steel pellet company the following describes operations at the national steel pellet company, an iron ore mining and processing facility located on the mesabi iron range of minnesota. Shows how iron ore, limestone, and coke are handled and prepared for the blast furnace in the making of iron. Blast furnace ironmaking an overview sciencedirect topics.
They can be up to 60 metres 200 ft tall and 15 metres 49 ft in diameter. The most common ore of iron is called haematite ironiii oxide. The raw ore is removed from the earth and sized into pieces that range from 0. Blast refers to the combustion air being forced or supplied above atmospheric pressure in a blast furnace, fuel, ores, and flux are continuously supplied through the top of the furnace, while a hot blast of air sometimes with. Iron and steel industries consumes enormous amount of energy and contributes significantly in carbon dioxide emission. In addition, no sinter and therefore no sinter plant is necessary for optimal operation. Where a cooling tower exists, our cooling fans are an important way to remove heat. The blast furnace has charging arrangements at the top and means of running off the pig iron and slag at the. We demonstrated our enormous capabilities for providing largescale blast furnaces by construction of no. Coke production for blast furnace ironmaking by hardarshan s. For example, at a large ironworks with an output of 7 million tons of raw steel a year, around 570 million tons a year of converter gas is generated, which is the equivalent of m 3. Slag is used in road making and as slag cement a final ground slag which can be used in cement, often mixed with portland cement. Extraction of iron metallurgy blast furnace and reactions. A blast furnace is a gigantic, steel stack lined with refractory brick where the concentrated iron ore, coke, and limestone are dumped from the top, and a blast of hot air is blown into the bottom.
Kinetics and modeling of ironmaking blast furnace overview the ironmaking blast furnace is a complex multiphase flow reactor. The transport phenomena and physical status in the hearth of an iron making blast furnace are very complicated and difficult to monitor and characterise. Step 2a the blast furnace the sinter is added through a hopper at the top of the blast furnace. Geologists recognise various types of iron ore, classified chiefly according to iron fe content see table 1 below. A blast furnace works by blasting hot air up through the furnace while fuels, limestone, and ore move continuously through the top of the furnace. The typical iron oxide mix for corex is 30% lump ore and 70% pellets. Wrought iron is quite soft and easily worked and has. Mar 20, 2017 shows how iron ore, limestone, and coke are handled and prepared for the blast furnace in the making of iron. Describes the principles of the blast furnace process and especially the control of the process. The iron is eliminated from the blast furnace as a special metallic material called pig i ron, with a high level of carb on and impurities in its compositio n. The majority of pig iron produced by blast furnaces undergoes further processing to reduce the carbon content and produce various grades of steel used for tools and construction materials. Iron making blast furnace iron making blast furnaces. The principle of blast furnace operational technology and.
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