Hot stoves work as countercurrent regenerative heat exchangers. 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 hot liquid slag is made into slag granules by means of high. The use of hot riquetted iron hi in the last furnace f. Blast furnace produces hot metal liquid iron using iron ore, coke, sinter. Co 2 abatement in the iron and steel industry 5 steel is basically an alloy consisting of iron, 0. Jan 10, 2016 then came the change from cold blast, charcoal furnaces to hot blast, coke furnaces in the mid1800s which brought iron making into the modern era.
Our technology base covers the entire blast furnace process route from hot blast and raw material handling, through the furnace and casthouse, to gas cleaning and hot metal slag processing. Iron ore is usually a mixture of iron and vast quantities of impurities such as sand and clay referred to as gangue. Till 1990, the blast furnace route of ironmaking had about 97% 527mt share of global iron production. Hot metal is led to hot metal ladlestorpedoes placed below the cast. The furnace is cooled with water running inside part of the case and bricks. The hot liquid slag is made into slag granules by means of high pressure. A high quality coke should be able to support a smooth descent of the blast furnace burden with. How iron is made material, manufacture, making, history. Danieli corus has enjoyed an incredible journey with indian steel industry over the years. The bentonite improves the cold and hot strength of the briquette. Optimum nut coke for the iron making blast furnaces. 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 hot rolled bars rods tube rounds rails slab billet bloom hot rolled and coldrolled strip coils structural shapes. By the middle of the 16th century, blast furnaces were being operated more or less continuously in southeastern england. Blast refers to the combustion air being forced or supplied above atmospheric pressure.
The iron ore concentrate is now mixed and ready for the pelletizing process. Mini blast furnaces mbf are generally viewed as miniature versions of the conventional large blast furnaces bf. The molten iron is tapped off the very bottom of the blast furnace and cast into hot metal or pig iron ingots. Mar 20, 2017 shows how iron ore, limestone, and coke are handled and prepared for the blast furnace in the making of iron. Sudheer steel making value chain steel making flow line steel making flow line finishing history and evolurtion what is iron making. Now there are nearly 700 blast furnace available in world. The metallic iron produced by such a furnace contains a relatively high proportion of carbon 4% and is passed to the steelmaking process as a liquid at approximately 1450c, called hot metal. Pdf iron and steel making is one of the most intense energy consuming in the industrial sectors. The production of iron from its ore involves an oxidationreduction reaction carried out in a blast furnace. T, burla person involved name designation and email.
The process is continuous with raw materials being regularly charged to the top of the furnace and molten iron and slag being tapped from the bottom of the. Us5395441a revert briquettes for iron making blast. Blast furnace ironmaking an overview sciencedirect topics. 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. Department of material science and metallurgical engineering, manit bhopal. Improvement made in blast furnace technology 1 hot metal production rate 80000tpd. Cost effectiveness analysis of hyl and drex dri te chnologies for the iron and steelking industry pa ge 7 steel making process and co 2222 emissionsemissionsemissions steel is primarily made by one of two processes. Either way, the fundamental activity in iron making involved a worker stirring small batches of pig iron and cinder until the iron separated from the slag. The blast furnace is a countercurrent gassolids reactor in which the descending column of burden materials coke, iron ore and fluxesadditives reacts with the ascending hot gases.
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. Smelting reduction of oxide ores with carbon as a reducing agent. Aug 04, 2011 the purpose of a blast furnace is to chemically reduce and physically convert iron oxides into liquid iron called hot metal. Pig iron blast furnace route international iron metallics. The purpose of a blast furnace is to chemically reduce and physically convert iron oxides into liquid iron called hot metal. Needing a larger supply of pig iron he leased the blast furnace at coalbrookdale in 1709. Blast furnace iron making raw materials blast furnace reaction. 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. Hot metal blastfurnace iron most blast furnaces are linked to a basic oxygen steel plant, for which the hot metal typically contains 4 to 4. The principal function of a blast furnace is to continuously produce liquid hot metal viz. However, the sharp drop in gas prices due to the marcellus shale development has led to resurgence in interest in gas based dri production. Blast furnace tapping practice at arcelormittal south africa, vanderbijlpark works p. His pots were thinner and hence cheaper than those of his rivals. The iron found in iron ores are found in the form of iron oxides.
In process of iron making, hot stoves are often used to preheat air which is used in the blast furnace bf. In 1707, abraham darby i patented a method of making cast iron pots. An iron making blast furnace revert briquette composition including finishing mill scale, steelmaking slag, blast furnace dust and a binder wherein the binder includes portland cement, granulated blast furnace slag cement or mixtures thereof and bentonite. Increased iron production led to a scarcity of wood for charcoal and to its subsequent replacement by coal in the form of cokea discovery that. Blast furnace products and there use size of blast furnace design of blast furnace is evolved through experience. Alternative methods known as direct reduction are used in over a score of countries, but less than 5 percent of iron is made this way. Com 03 using thermocouples in furnace measurements blast furnaces heat iron ore to produce the iron required as a raw material for steel making. Historically, iron was produced by the hot blast method, or later, the anthracite furnace. 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. Larger blast furnace, use of better prepared burden, recovery of waste energy, and maximum recovery of slag characterize the iron making technology proposed for vsp. 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. Principles of blast furnace iron making theory and. Pdf optimum nut coke for the iron making blast furnaces.
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. Presentation at edrc kolkata on 14th feb 2007 by n. Compared to this, elsewhere furnaces up to 5070 m 3 had been built. Lowering iron losses during slag removal in hot metal desulphurisation without using fluoride. 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. Us5395441a revert briquettes for iron making blast furnace. Coke is the most important raw material fed into the blast furnace in terms of its effect on blast furnace operation and hot metal quality. Extraction of iron metallurgy blast furnace and reactions. Blast furnace simple english wikipedia, the free encyclopedia. Handling of hot metal in blast furnace iron making ispatguru. Pdf technological changes in blast furnace iron making. Silicon and aluminum often occur in iron ores as quartz, aluminum silicate clay minerals, or gibbsite.
As the mixture of iron ore, coke and limestone heats, the hot waste gases are collected and cleansed. Blast furnace tapping practice at arcelormittal south. Main differences from the blast furnace route the main differences between corex and a conventional blast furnace route are. 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. This furnace will be the indias largest blast furnace to date. Ironmaking 101 from ore to iron with blast furnaces. The process is continuous with raw materials being regularly charged to the top of the furnace and molten iron and slag being tapped from.
Major impurity elements in iron ore that can affect the quality of iron produced in a blast furnace and the efficiency of blast furnace ironmaking are silicon, aluminum, phosphorus, and sulfur. In lecture 31 a simplified material balance is considered for ironmaking blast furnace and the results of material balance formulation are presented in the form rist diagram in that it is considered that charge consists of pure iron oxide and coke and the product is hot metal containing carbon only. While blast furnace operators aim to enrich the hot blast. 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.
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. Process monitoring of ironmaking process in a blast. Blast furnaces are used to produce pig iron from iron ore for subsequent. It is liquid in nature and gets collected in the hearth of the bf. A blast furnace is usually built with a steel case and bricks made of magnesium oxide or other refractory material inside the case. The intensive utilization of fossil carbon in the ironmaking blast furnace bf is related directly to co2 emission and global warming. While blast furnace operators aim to enrich the hot blast with oxygen, corex already uses highpurity oxygen. The hot stoves typically use low calorific blast furnace gas bfg combined with higher calorific value cove oven gas cog. Nonblast furnace iron making technology total materia. The primary objective of iron making is to release iron from chemical combination with oxygen, and, since the blast furnace is much the most efficient process, it receives the most attention here. Those making use thereof or relying thereon assume all risks and liability arising from such use or reliance. 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. This book describes the principles of the blast furnace process and especially the control of the process. 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 cleaned blast furnace gases are used to preheat stoves and boilers within the steel plant. It has a wide range of properties that are largely determined by its chemical composition carbon and other alloying elements. Efficient and environmentally friendly smelting reduction a vai ironmaking technology. Calculation of blast furnace size is empirical in nature. The better understanding of iron making reactions and improved equipment evolved into the harddriving furnace operation centered in the 1880s to 1900s. The largest blast furnace in india at that time was of 2000 m 3. The principle of blast furnace operational technology and. 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. The large, refractory lined furnace is charged through its top with iron as ore, pellets, andor sinter. 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. Corex is the first commercially operating alternative to the blast furnace for hot metal production, and hismelt is the worlds first commercial smelting process for making iron straight from the ore. Nonblast furnace iron making technology total materia article. All the three ingredients are crushed into small round pieces and mixed and put on a hopper which controls the input. 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. At the furnace bottom, where molten pig iron is held, low liquid permeability at the center of. Primetals technologies has provided blast furnace engineering, project excellence and expertise to customers worldwide for over a century. This furnace is designed for a twenty year campaign. Stoves absorb heat from the combustion of blast furnace gases with air and transfer this heat to the air blast that will be injected into the blast furnace tuyeres.
The burden charge consisting of iron oxide, flux and coke and it provides through the throat from the top of the furnace. Shows how iron ore, limestone, and coke are handled and prepared for the blast furnace in the making of iron. Iron making in mini blast furnace mbf the blast furnace ironmaking process had, until recently, been the unchallenged method of making hot metal on a large scale. Principle of iron making by blast furnace by a k biswas download free ebooks online.
Blast furnaces are used continuously and are only shut down when their brick lining needs replacing. 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. During the process of iron making, the impurities are fluxed and removed as slag. In the blast furnaces bf liquid iron popularly termed as hot metal is. Interaction reaction between the degradation of coke and the reduction of iron ore in oxygen blast furnace under hydrogenenriched operation.
May 03, 2010 the iron making blast furnace itself is built in the form of a tall chimneylike structure lined with refractory brick. A world class blast furnace operation demands the highest quality of raw materials, operation, and operators. The liquid iron and molten slag flows to the bottom of the blast furnace while the slag floats on top of the molten iron and is drawn off separately. India as a 4th steel producer in the world has resulted due to adaptation of new technologies in the field of iron and steel making since from the last few decades.
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