The principle of blast furnace operational technology and. Creating steel from lowgrade iron ore requires a long process of mining, crushing. 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. It is the upgraded tier of the crude blast furnace. Analysis of slag flow in blast furnace during the extraction. Ios press ebooks modern blast furnace ironmaking an. Blast furnaces were utilized for smelting and refining industrial metals, generally iron, and were widely used in the creation of steel in the pittsburghwestern pennsylvania region during the united states 20th century industrial boom. Consequently, rich iron ore andor iron oxide pellets formed from concentrate can be added directly to a blast furnace see iron production. State of direct reduction and reduction smelting processes j. Competition in industry drives higher production rates. Blast furnace, prediction, flame temperature, artificial neural. 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.
Iron blast furnace is a vertical shaft, which is used to melt the iron ore and to produce hot metal by heat exchange and chemical reaction. Chemistry extraction of iron in blast furnace egogy. The book focuses on the control of the blast furnace process with respect to thermal control, gas flow control and casthouse operation. Protection mechanisms for blast furnace crucible using titanium. Production of pig iron in a blast furnace chapter division basic terms description of a blast furnace plant main parts of a blast furnace, description and function composition of a charge in the production of pig iron in a blast furnace. Most of the iron ore bodies commercially explored consist of iron oxides. Iron making and general industry technologies iron making technologies 45 3a2. Field tests of the introduced technology had been performed abroad. How a blast furnace works introduction the purpose of a blast furnace is to chemically reduce and physically convert iron oxides into liquid iron called hot metal. Ironmaking 101 from ore to iron with blast furnaces. The smelting of iron ore into metallic iron was first accomplished by primitive blast furnaces approximately three thousand years ago. The cupola can run continuously as are blast furnace, but in practice it may works when required. Coke is cheap and provides both the reducing agent for the reaction and also the heat source.
It has a very low heating value, about 93 btucubic foot 3. Induction and arc furnaces use electricity to melt steel and cast iron. Blast furnace economics are such that larger units have lower unit production costs, hence there has been a trend to bigger and bigger furnaces. After mining, various kinds of iron ores are brought to the blast furnace which is the starting process for refining iron ores or mined ores and for the production of pig iron. Iron was produced at nassawango until 1847 when lack of labor and poor market conditions caused spence who fell into financial ruin to shut down the furnace. This page looks at the use of the blast furnace in the extraction of iron from iron ore, and the conversion of the raw iron from the furnace into various kinds of steel. This book describes the principles of the blast furnace process and especially the control of the process. Theory and practice presents theoretical, experimental, and operational evidence about the iron blast furnace as well as a mathematical description of its operation. 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. Modern furnaces are highly efficient, including cowper stoves to preheat the blast air and employ recovery systems to extract the heat from the hot gases exiting the furnace.
The extraction of iron from its ores is quite a technical process. The blast furnace is a huge, steel stack lined with refractory brick, where iron ore, coke and limestone are dumped into the top, and preheated air is blown into the bottom. The electric furnace is used to make steel, stainless steels, ferroalloys, and special alloys, whereas ferromanganese is often made in blast fur naces. Extraction of iron blast furnace extraction of iron blast furnace skip navigation sign in. Manufacture of iron by blast furnace process 988 words. In the blast furnace, it is so hot that carbon monoxide can be used to reduce the iron oxide in place of carbon. This book discusses the importance of blast furnace process as a complete operation. Part of the gas cleaning system of a blast furnace in monclova, mexico. Draw a diagram of the blast furnace used in the extraction of iron and label the parts. The burden charge consisting of iron oxide, flux and coke and it provides through the throat from the top of the furnace. The blast furnace is the main ironmaking production unit in the world which converts iron ore with coke and hot blast into liquid iron, hot metal, which is used for. Noncoking coal can be used directly as a reducing agent and energy source up to 80% of the iron oxide fraction can be lump ore.
Pdf technological changes in blast furnace iron making in. Blast furnaces are used continuously and are only shut down when their brick lining needs replacing. Blast refers to the combustion air being forced or supplied above atmospheric pressure. Extraction of iron metallurgy blast furnace and reactions.
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. After iron ore is mined it is send to the blast furnace. 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. Theory and practice pdf adobe drm can be read on any device that can open pdf adobe drm files. The reducing gas from 1020% co and 8090% h2 is produced from natural gas. Extraction of iron in a blast furnace the significant reactions occuring within the blast furnace can be described via the following steps showing how the reducing agent varies depending on the height in the furnace i. A typical blast furnace along with its various parts is shown in fig. In the combustion heat accumulation phase, heat energy in hot exhaust gas from a burner is accumulated in checker bricks and, in the ventilation phase, a large quantity of air is blown through the checker bricks to raise the temperature of the air. Most furnaces use liquid fuel, gaseous fuel or electricity as energy input. All the three ingredients are crushed into small round pieces and mixed and put on a hopper which controls the input. Originally, the iron was collected in pools called pigs, which is the origin of the name pig iron. The charge for agglomerate production comprises three basic parts.
A hot blast stove is a facility to supply hot air to a blast furnace continuously. Oilfired furnaces mostly use furnace oil, especially for reheating and heat treatment of materials. As slag leaves the blast furnace in a molten form at1500c it is a homogeneous material free from foreign matter. Pdf blast furnace bf ironmaking is one of the most important production links in modern iron steel making. Now there are nearly 700 blast furnace available in world. Blast furnaces used in the isp have a more intense operation than standard lead blast furnaces. These practices, as conventional operation of iron and steelmaking installations, present both advantages as well as undesirable consequences. Overview of the steelmaking process pellets sinter limestone coke iron ore coal scrap blast furnace ironmaking converter steelmaking ladle refining blast furnace steelmaking coalnatural gas plate hotrolled bars rods tube rounds rails slab billet bloom hotrolled and coldrolled strip coils structural shapes.
The principles, operation and products of the blast furnace. Composition of a charge in the production of pig iron in a blast furnace agglomeration and pelletization of iron ores requirements to individual components of a blast furnace charge time for the. Iron works are located close to coal fields so that plentiful of coal is available at cheap rate. The blast furnace bf is the heart of the integrated iron and steel industry. Basically, the blast furnace is a counter current heat and mass exchanger in which rising reduction gas loses most of its heat on the way up, leaving the furnace at a temperature of about 200. New pellets were traditionally developed in the laboratory and tested in a production blast furnace. Blast furnace an introduction blast furnace is the focus of any integrated steel plant. The properties of the original raw ore are changed in this process. Pulverized coal injection for blast furnaces pci technology overview. Pig iron and refined iron ore pellets briquetted iron can also be used, and because his t. Types of blast furnace slag j blast furnace slag in australia is produced in. Pdf on jan 1, 2012, seongho lee and others published calcium ion extraction from blast furnace slags for the synthesis of pure calcium carbonate polymorphs by accelerated carbonation find. The production of iron is accomplished by smelting of ores, pellets, and sinter in blast furnaces with subsequent refining of molten iron and scrap in oxygenblown processes. Lkabs experimental blast furnace for evaluation of iron ore products.
The iron ore concentrate is now mixed and ready for the pelletizing process. The tapped product liquid hot metal is equivalent in quality to the hot metal produced in a blast furnace or corex plant. As the mixture of iron ore, coke and limestone heats, the hot waste gases are collected and cleansed. The blast furnace remains an important part of modern iron production. Principle of iron making by blast furnace by a k biswas download free ebooks online. The furnace gets its name from the method that is used to heat it. Comparative performance evaluation of blast furnace. Manufacture of iron by blast furnace process iron is a naturally occurring element in its ore form haematite, however for iron to be of any use the impurities must be removed.
Nov 24, 2012 extraction of iron blast furnace extraction of iron blast furnace skip navigation sign in. Finery forges were used as early as 3rd century bc, based on archaeological evidence found at a site in tieshengguo, china. In the upper part of the blast furnace see figure 1. Theory and practice presents theoretical, experimental, and operational evidence about the iron blast furnace as well as a mathematic, isbn 9780080232584. Pdf in this research, ammonium chloride was used to calcine tiextraction blast furnace slag ebfs with the aim of removing iron from it. Blast furnace, a vertical shaft furnace that produces liquid metals by the reaction of a flow of air introduced under pressure into the bottom of the furnace with a mixture of metallic ore, coke, and flux fed into the top. It is suitable for students of metallurgy as well as for blast furnace operators and management.
The reactions of the blast furnace involve 1 combustion of the fuel and its conversion into carbon monoxide, 2 reduction of the ore. Modeling of burden distribution in the blast furnace doria. A variety of processes take place within the blast furnace, as the stock slowly moves downwards and temperatures increase. Modern blast furnaces produce more than 10,000 tonnes per day. The dri fines are processed to hotcompacted iron, transferred to a charging bin positioned above the melter gasifier and then charged into the melter gasifier, where melting takes place. This book includes a set of equations that accurately describe stoichiometric and enthalpy balances for the process and which are consistent with observed. Considering the differences in facility configurations and. Improvements in the process over many centuries eventually led to the mass production of iron and to the industrial revolution. Extraction of iron in a blast furnace iron is also below carbon in the reactivity series, so therefore carbon can be used to reduce it note. The flowcharacteristic of blast furnace slags is strongly influenced by the extent of reduction of iron oxide at low temperature in the granular zone besides being influenced by the composition, and the quality and the quantity of the gangue in the iron bearing materials. Process analysis for blast furnaces by the discrete element method. Iron ore, limestone and coke is the stock of the blast furnace.
Pdf kinetics of iron removal from tiextraction blast. The blast furnace is a cylindrical tower like structure about 25m to 35m high. Technological changes in blast furnace iron making in india since last few decades article pdf available in international journal of science and research ijsr 212. The iron ore is first roasted in air to produce iron iii oxide which is mixed with coke and limestone and then further heated to a very high temperature in a blast furnace.
Ad 31, who applied the power of waterwheels to pistonbellows in forging cast iron. A study of the flow characteristics of blast furnace slag is important to record the softening and melting phenomena in blast furnace which greatly influence the extent and location of the cohesive zone having a direct say on the blast furnace operation, quality of hot metal and the coke consumption. Coke is produced by heating coal in the absence of air. As a starting point, the blast furnace is seen as a simple iron ore smelter, while gradually the physical, chemical and metallurgical background of the blast furnace process is clarified. The most common ore of iron is called haematite iron iii oxide. The 70 million net tons of steel recycled in 2000 were used to produce about 112 million net tons of new steel in the united states. Pdf calcium ion extraction from blast furnace slags for the. Reaction of zone of fusion in blast furnace definition. The melting period does not exceed 4 hours in most of. Air heated in the blast furnace stoves, is applied from the bottom of the. Main differences from the blast furnace route the main differences between corex and a conventional blast furnace route are. Well regarded as the authorative text of blast furnace twostage modelling, every metallurgist in the iron and steel industry should have one and understand it. A finery forge is a forge used to produce wrought iron from pig iron by decarburization.
It is lined with refractory firebricks that can withstand temperatures approaching 2000 o c. The effectiveness of the chinese blast furnace was enhanced during this period by the engineer du shi c. Preheated air at about o c is blasted into the furnace through nozzles near its. The improved blast furnace is a multiblock machine added by immersive engineering. The chemistry of desulphurisation has been very actively investigated in recent years3,6. Blast furnace is used to reduce the iron ore to iron.
The use of hot riquetted iron hi in the last furnace f. Theory and practice presents the significant role of iron blast furnace by which iron is efficiently and rapidly reduced from ore and it is the basis for all primary steelmaking. Melting furnaces for nonferrous materials use fuel oil. As evidence of the rtas commitment to the increased use of. It is used in road making, cement manufacturing a light weight building materials. Calculation of blast furnace size is empirical in nature. Blast furnaces are used to produce pig iron from iron ore for subsequent. The main purpose of sintering of iron ores agglomeration is to convert fine raw materials into lumpy material for pig iron making in the blast furnace. Blast furnace products and there use size of blast furnace design of blast furnace is evolved through experience. Blast furnace operation at a glance the purpose of a blast furnace is to chemically reduce and physically convert iron oxides into liquid iron called hot metal.
Blast furnace produces hot metal liquid iron using iron ore, coke, sinter. Pig iron is converted into cast iron by heating molten pig iron with scrap iron and coke in specially designed furnaces. Milestones of our blast furnace operation technologies tamura categorized our history of pig iron making into the following three periods, in an article. Donald wagner suggests that early blast furnace and cast iron production evolved from furnaces used to melt bronze. This is done by a process involving a blast furnace.
Limestone is used to remove impurities such as slag. These materials are loaded into the blast furnace from the top while a blast of hot air is introduced into it from beneath via small pipes known as tuyeres. 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 blast furnace process is primarily used in the carbothermic reduction of oxides, such as iron, zinc, and lead. The use of hot riquetted iron hi in the last furnace f for hot metal production hi can be used as blast furnace burden material with the following environmental, productivity and cost benefits. Bw pdf download a blast furnace is a type of metallurgical furnace used for. They can be up to 60 metres 200 ft tall and 15 metres 49 ft in diameter.
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. 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. The common ores of iron are both iron oxides, and these can be reduced to iron by heating them with carbon in the form of coke. Extraction of iron in a blast furnace reduction haematite o. Draw a labelled diagram of blast furance for the extraction of iron. Sulphur control in blast furnace low sulphur in hot metal ensures lower inclusion content and enables to achieve better mechanical properties such as hot workability, impact and ductility values. Extracting iron from iron ore using a blast furnace. Using coal coke immersive engineering for fuel, it converts iron ingots and blocks into steel.
However, if fine ore ere to be used as feed to a blast furnace its powdery nature would restrictw the passage of the blast air up through the furnace. This book focuses on the control of the blast furnace process with respect to thermal control, gas flow control and casthouse operation. Improved blast furnace official feed the beast wiki. The process involved liquifying cast iron in a fining hearth and removing carbon from the molten cast iron through oxidation. Ironmaking in a blast furnace takes place by charging sinter in the form of agglomerated iron ore and coke in the form of agglomerated coal from the top of the. How pig iron is converted into iron and steel in blast. The charge, which consists of iron ore, coke and limestone etc. Pdf fault identification for quality monitoring of. Describes the principles of the blast furnace process and especially the control of the process. C, while descending iron oxides are wholly converted to metallic iron walker, 2000.
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