Pdf file click here for printable worksheet a simplified diagram of a blast furnace is drawn below. The blast furnace 9 the structure of the blast furnace 9 the ironmaking process 11 no. 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. Why does iron have to be extracted in a blast furnace iron can be extracted by the blast furnace. The purpose of a blast furnace is to chemically reduce and physically convert iron oxides into liquid iron called hot metal. Extraction of iron in a blast furnace reduction haematite o. Production of pig iron in a blast furnace 9 scheme of a blast furnace content a blast furnace charge and its treatment a blast furnace charge consists of ore, fluxes and fuel.
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. Ore, limestone and carbon in the form of coke are put into the top of the blast furnace in layers. The production of iron in a blast furnace is a continuous process. Energy analysis of a blast furnace system operating with. This auxiliary equipment and the gaseous pathways inside a blast furnace process are shown in figure 2. Ssab tunnplat in lulea had two blast furnaces in operation until june 2000. A blast furnace is a special type of furnace for smelting iron from ore.
Introduction blast furnace is the mostly applied facility for the pig. The choice of pellets in a mixed blast furnace burden and how. This continuous run of the blast furnace is known as campaign life. The blast furnace process blast furnace process 18. The optimal interaction between sophisticated models and the expert system provides extended assistance to plant operators and minimizes the risk of human errors. The coke rate of large blast furnace has already contained nut coke fig. The blast furnace process for the production of iron is of paramount importance because it. The bottom cylindrical part of the profile is called a hearth, wherein pig iron and slag. At sufficiently high temperatures, the carbon can participate directly in the. The process of mining lowgrade iron ore, or taconite, requires massive resources. Blast furnace simple english wikipedia, the free encyclopedia. In order to operate a blast furnace stably and economically, it is important to form an inversev shaped, cohesive zone in the high ore coke cohesive zone central gas improvement of liquid permeability in deadman formation of cohesive zone as inverse v shape deadman deadman.
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. Step 2c the blast furnace the furnace is run continuously for up to 2 years. Methods of shutting down a blast furnace ispatguru. All the three ingredients are crushed into small round pieces and mixed and put on a hopper which controls the input.
Logicalmathematical evaluation model of blastfurnace melting. Learn more who are renowned for creating steel using a blast furnace process and very short step from the blast furnace. Moreover, using nut coke in blast furnace could also improve the utilization efficiency of resources, and indirectly save the energy con sumption during coking process. Energy analysis of a blastfurnace system operating with. The blast furnace bf is the most widely used ironmaking. 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 has auxiliary equipment associated with it. Chemistry of the ironmaking by blast furnace process ispatguru. Blast furnaces differ from bloomeries and reverberatory furnaces in that in a blast furnace, flue gas is in direct contact with the ore and iron, allowing carbon monoxide to diffuse into the ore and reduce the iron oxide to elemental iron mixed with carbon.
As the mixture of iron ore, coke and limestone heats, the hot waste gases are collected and cleansed. The blast furnace operates as a countercurrent exchange process whereas a bloomery does. 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. Figure 2 a shows a schematic diagram of blast furnace interior. A variety of processes take place within the blast furnace, as the stock slowly moves downwards and temperatures increase. The book focuses on the control of the blast furnace process with respect to thermal control, gas flow control and casthouse operation. Blast furnaces are used continuously and are only shut down when. The effect on blast furnace process of changed pellet size. Stateoftheart computational fluid dynamics model optimizes fuel rate in.
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. The origin is lost in antiquity, however, generally it means covering a fire with ashes or fresh fuel to restrict air, reducing the combustion rate, and. At the same time, hot air called wind is blown inside the furnace. 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. This is exactly what carbon can do as a reducing agent. 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. 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 softening and melting of blast furnace burden materials. Blast furnace and process description chemical engineering. 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 furnace, while blowing hot blast into the furnace bottom. The carbon is fed to the blast furnace in the form of coke pyrolyzed coal from the coking plant. Blast furnace process an overview sciencedirect topics.
Iron oxides, flux agents, and metallurgical coke are added to a skip car at the stock house. The principle of blast furnace operational technology and. Iron making in the furnace usually continues for about ten years before the furnace linings have to be renewed. May 05, 2015 methods of shutting down a blast furnace a blast furnace, after it is blown in and the production of hot metal starts, runs for a large number of years before it is put down for relining. This book describes the principles of the blast furnace process and especially the control of the process.
Pdf blast furnace in engineering education researchgate. Pdf using blended learning method, blast furnace subject was analysed inside the didatec project. A high quality coke should be able to support a smooth descent of the blast furnace burden with. Agglomeration techniques with sintering and pelletising in details. 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. Jul 12, 2019 blast furnace and process description. Liquid iron hot metal is produced in a blast furnace from the burden materials through a series of chemical reactions which are taking place at various levels in a blast furnace. Blast furnace simulation download ebook pdf, epub, tuebl. 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.
Request pdf blast furnace process the objective of the blast furnace bf is to produce hot metal. Nippon steel corporation has developed many different blast furnace modelsthe onedimensional. A world class blast furnace operation demands the highest quality of raw materials, operation, and operators. Nippon steel corporation has developed many different blast furnace modelsthe one dimensional. Analysis, control, and optimization uses a fundamental first principles approach to prepare a blast furnace mass and energy balance in excel. 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. At the same time the experimental blast furnace was available for pellet testing and it has been invaluable in the development process. They have thick steel sides, lined with refractory bricks, to ensure that heat is not lost. Step 2d the blast furnace when running continuously, iron is run out. The blast furnace unit has a blast furnace of 350 cum capacity of producing 227500 mt of hot metal per annum. Optimizing blast furnace operation to increase efficiency and. The blast furnace process can be briefly described as follows.
Chemistry of the ironmaking by blast furnace process. A typical blast furnace may be up to 32 metres in height and 10 metres in diameter. The word banking is used because of a similarity to the operation of banking a fire. The blast furnace process control system in combination with the blast furnace optimization system creates the next level in intelligent blast furnace automation. The burden charge consisting of iron oxide, flux and coke and it provides through the throat from the top of the furnace. Iron oxides, flux agents, and metallurgical coke are. The blast furnace is a huge, steel stack lined with refractory brick. Profile of a blast furnace and its dimensions are adapted to technology of process, see figure. Extraction of iron metallurgy blast furnace and reactions. Heavy industrial mining equipment, expansive mines, and a skilled labor pool.
Pdf using blended learning method, blast furnace subject was analysed inside. Aug 04, 2011 the purpose of a blast furnace is to chemically reduce and physically convert iron oxides into liquid iron called hot metal. Modern blast furnace ironmaking 3rd edition pdf ammedicine. Blast furnaces are used continuously and are only shut down when their brick lining needs replacing. Process analysis for blast furnaces by the discrete element method. The blast furnace ironmaking system using prereduced ore twostage reduction system is a twostage ore reduction system that consists of a process for prereducing iron ore by using natural gas or some other suitable energy containing a comparatively small amount of carbon and a blast furnace process for further reducing. This requires an element that binds oxygen more strongly than iron. 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. Nov 22, 20 blast furnace, co, reaction, slag, chemistry of the ironmaking by blast furnace process.
At the bo ttom of the furnace, the temperature is very high. Step 2b the blast furnace the inner lining is made of insulating bricks, designed to reduce heat loss through the outer walls of the furnace. Ironmaking blast furnaces consist of several zones. The method used in blast furnaces have been used since the 1500s. They can be up to 60 metres 200 ft tall and 15 metres 49 ft in diameter. Firstly, the carbon in the blast furnace burns with the hot air to form carbon dioxide. High energy efficiency and productivity are achieved in the process by a countercurrent moving bed.
The ore part of a charge consists of iron ores and concentrates, manganese ores and various types of scrap containing iron. Blast furnaces produce pig iron from iron ore by the reducing action of carbon supplied as coke at a high temperature in the presence of a fluxing agent such as limestone. A major advance in bf ironmaking has been the use of pulverized coal which partially replaces. Blast furnaces may have the following ancillary facilities. Chemistry extraction of iron in blast furnace egogy. The samples represent the material entering the blast. Analysis, control, and optimization uses a fundamental first principles approach to prepare a blast furnace mass and energy balance in exceltm. The furnace is heated constantly and is recharged with raw materials from the top while it is being tapped from the bottom. Banking process in the blast furnace is adapted, since the procedure of banking is useful for short outages. Process analysis for blast furnaces by the discrete. Two different pellet bins are emptied and pellet samples are taken at the outlet side of the screen. The choice of pellets in a mixed blast furnace burden and. Primary steel making includes converting liquid iron from a blast furnace and steel scrap into steel via basic oxygen steel making or melting scrap steel andor direct reduced iron dri in an electric arc.
The only effect that can be seen on the blast furnace process is a decrease in gas utilisation of two units. Robust descriptions of the main equipment and systems, process technologies, and best practices used in a modern blast furnace plant are detailed. 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. Optimizing blast furnace operation to increase efficiency. The blast furnace is a tall, vertical shaft furnace which uses coke to reduce. Jun 21, 2016 modern steel making process uses a blast furnace for manufacturing steel. Special nozzles called tuyeres are used to put the air in the furnace. Mar 31, 2014 the purpose of a blast furnace is to reduce and convert iron oxides into liquid iron called hot metal.
High pellets ratio operation forced by burden material restrictions at kobe steel resulted in the development of a center coke charging process based on. Download pdf blastfurnaceironmaking free online new. This reaction produces a lot of heat, and is the main source of heat in the furnace. Iron ore, limestone and coke is the stock of the blast furnace. Development of mathematical model of blast furnace nippon steel. Iron ore, coke and limestone are put into the top, and preheated air is blown into the bottom. This auxiliary equipment and the gaseous pathways inside a blast furnace process are shown in fig. The iron ore concentrate is now mixed and ready for the pelletizing process. 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. A blast furnace is usually built with a steel case and bricks made of. The formation of iron and steel the blast furnace 2. Blasts furnaces are used for smelting during the production of metals such as iron, lead, zinc, and copper. The iron in the processed ores must be dissolved out by chemical processes. 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.
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