Blast refers to the combustion air being forced or supplied above atmospheric pressure. Pdf estimation of state of the blast furnace crucible. Blast furnace busted very dangerous above 45mtr height. Us3341188a us460896a us46089665a us3341188a us 3341188 a us3341188 a us 3341188a us 460896 a us460896 a us 460896a us 46089665 a us46089665 a us 46089665a us 3341188 a us3341188 a us 3341188a authority us. Typical blast furnace internal hearth 3d geometry no refractory. The principle of blast furnace operational technology and. At present, in some plants, the breakout of blast furnace hearths takes place very often. Allied mineral products, formerly riverside refractories, offers a variety of mixes including, gunning, pumping, and shotcrete, for the blast furnace industry. Carbon and graphite refractories are primarily used for blast furnace linings because of their high temperature conductivity and their ability to reduce the heat load by moving the excessive heat to the shell where the heat can be. 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. In 1910, a 10company merger created harbisonwalker refractories company, a 33plant operation. Of the several operating cases, the one in which the heater duty is the highest, shall be regarded as the normal case.
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. It should be operated not less than 15 years during one campaign. 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. The raw materials require 6 to 8 hours to descend to the bottom of the furnace where they. The estimation was based on temperatures of thermocouples placed in control boreholes on three levels of. Refractories are inorganic, nonmetallic, porous, and heterogeneous. Refractory lining an overview sciencedirect topics. The refractory lining is cooled to further enhance the protection against the.
Current refractory technology and practices in the. To get good campaign life special attention must be given to both refractory lining and design i. Blast furnace trough materials trough mix the flow rate of molten metal and slag through the trough system increase many times in case of larger blast furnaces. Blast furnace construction attaches great importance to the design rationality of furnace bottom and furnace hearth. After a period of accumulation, flow is reversed, and the hot stove is used. Pdf preparation of ceramicbonded carbon block for blast. Principles for blast furnace refractory lining inspection and. Furnaces and refractories fusion dust and slag or by the action of alkalies on fireclay refractories, to form alkalialumina silicates.
Any material expands when heat ed, and contracts when cooled. Having over 80 years of experience in the iron and steel refractory product industry, our vast collection of blast furnace lining refractories are tailored to any application you may require. Refractory wear rate is evaluated by considering the fluid flow speed at the refractory walls. It was shown that the deformation of aluminosilicate refractories depends not only upon temperature, load, and hold but also to. The charge, which consists of iron ore, coke and limestone etc. These properties, verified by internal testings, are merely indicative and. In 2009 a second partial repair was conducted in order to repair the refractory hearth lining around the. Monitoring and control of hearth refractory wear to improve blast furnace operation.
Typical blast furnace internal hearth 3d geometry no refractory visible. They have thick steel sides, lined with refractory bricks, to ensure that heat is not lost. Pdf wear mechanism for blast furnace hearth refractory. Blast furnace gas is produced during the iron oxide reduction in blast furnace iron making in which iron ore, coke and limestone are heated and melted in a blast furnace and is an indigenous process gas of the steelworks industry pugh et al.
Generally, adopt high alumina bricks, fireclay bricks and common carbon brick to build blast furnace lining, which results the short furnace life refractories used in blast furnace mainly include carbon brick, alumina silica refractory and etc. In the service of blast furnace hot blast stoves the lining and checkerwork fail in individual zones as the result of deformation of the refractories, formation of cracks, and chemical corrosion of the lining under the action of lowmelting dust at high temperatures. Therefore the key factor to expand the lifespan of the hearth is to improve the refractory quality 3. Harbisonwalker handbook of refractory practice 2005. Plasma furnaces have been successfully applied to the production ofa variety ofmaterials, particularly ferroalloys. Blast furnace gas has a high carbon monoxide co content and a low heating value, typical. Fritz w lurman, a well known blast furnace man of the time opined in 1892 that irrespective of the use of so called refractory materials, the best means of maintaining the walls of the blast furnace is with cooling water. Unless otherwise specified, the design duty shall be 110% of the furnace duty in the normal case. The stoves act to store heat from the blast furnace waste gases. Us5890805a method for monitoring the wear and extending. Blast furnace refractories blast furnace lining refactory. The effect of carbon aggregates on the carbon refractory properties for a blast furnace was studied with xray diffraction xrd, scanning electron microscopy sem, an energydispersive xray.
The typical campaign life of a modern blast furnace is 15 to 20 years, depending on the cooling and refractory design as a whole and the hearth area in particular. The method includes determining the wear line of the lining from signals of temperature probes embedded at spaced locations across the thickness of the refractory using a one dimensional heat transfer model to locate a first approximation of a. The refractory lining thickness of the blast furnace is in use as 650 mm. Blast furnaces are used continuously and are only shut down when their brick lining needs replacing. Iron making solutions to extend blast furnace lifetime. The regenerative chamber is filled with a checkerwork of refractory brick, heated by the burned gas. 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. With todays large blast furnaces, the main trend in hotblast stoves is toward high temperature and pressure ventilation with dome temperature around 1550. Industry news refractory, refractories, refractory supplier.
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. The refractory lining is cooled to further enhance the protection against the dispatch of excess heat that can destroy the refractory lining. The frequent maintenance is basically the effect of high corrosion and erosion of working lining castable. Extraction of iron metallurgy blast furnace and reactions. A method is provided for online monitoring of the wear of a refractory lining of a blast furnace and for extending the life of said lining. The blast furnace body is a huge structure of 50m in height, 20m in width. The hot blast system, incorporating either three or four hot blast stoves per blast furnace, is the other major refractory installation in the blast furnace complex. Ironmaking blast furnaces consist of several zones. Aug 15, 2014 refractory lining of blast furnace a modern blast furnace bf is refractory lined to protect the furnace shell from the high temperatures and abrasive materials inside the furnace. Blast furnace is used to reduce the iron ore to iron. Refractorylined blast furnace tuyere download pdf info publication number us3341188a. Simple 3d geometry figure 3 shows the geometry that is used for setting up the 3d cfd model. Best blast furnace refractory for sale in rongsheng manufacturer. They are typically composed of oxides of the following materials.
Blast furnace stack the refractory material is subjected to attack from co atmosphere, alkalines, and mechanical wear. Pdf estimation of state of the blast furnace crucible and. As the mixture of iron ore, coke and limestone heats, the hot waste. What furnace shape is most suitable from the furnace heat loss point of view. The refractory materials and refractory bricks used in diffreent parts of blast furnace are as follows.
Project standards and specifications page 7 of 33 rev. Pdf monitoring and control of hearth refractory wear to. All the three ingredients are crushed into small round pieces and mixed and put on a hopper which controls the input. The cyclic thermal conditions in the blast furnace hearth create a continuous hearth refractory wear mechanism via the repeat formation and spalling of the reaction layer. R e f r a c t o r i e s f o r b l a s t f u r n a c erefractories for blast furnace 3 the chemical physical properties of the products the tables hereinafter show the main average properties of the products. The feedstocks, oxygen, and steam are introduced through burners at the top of the gasifier. One of the attributing factors for higher downtime of furnace is the frequent maintenance of trough refractory working lining. This alliance offers, on a turnkey basis, single source supply and procurement options for complete blast furnace plants. This furnace has an historical rate production of 2.
Normal refractories have a fusion temperature of 1580 1780 c e. Principles for blast furnace refractory lining inspection. Cracks in the refractory lining of the furnace, filled with liquid metal, give a high conductivity path for leakage of heat from the furnace, with the result that if the leak reaches the outer steel shell, that portion of the shell becomes extremely hot, and may be dangerous to touch. The more refractory difficult to reduce materials, and those with high melting points. Choose suitable blast furnace brick or unshaped refractory materials for different region in the blast furnace based on the reason of erosion and breaking. For this emergency repair there was no time to reengineer the. The refractory bricks are produced in the great many shapes required for the correct lining of each. With todays large blast furnaces, the main trend in hot blast stoves is toward high temperature and pressure ventilation with dome temperature. Blast furnace has the advantages of large output, high productivity and low cost, which is unmatched by other ironmaking methods. They have the advantage ofallowing the direct use offine feed materials. Provides a large variety of refractory products together with the best value which include blast furnace construction materials such as taphole brick, tuyere, linings for shaft, belly, bosh, bottom, and also consumable materials such as taphole clay, trough castable, and furthermore include refractory construction materials for hot stove.
The principle of blast furnace operational technology and centralized gas flow by center coke charging. Refractory bricks used for different parts of blast furnace. The iron ore concentrate is now mixed and ready for the pelletizing process. Aug 04, 2011 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 remaining refractory thickness assessment of hearth part in the blast furnace. The primary aim for any blast furnace is to minimize the loss in production by reducing the downtime. Particular tolerances, if any, should be indicated at the time of the enquiry and be the subject of tender technical speci. Allied mineral products, formerly riverside refractories, offers a variety of mixes including, gunning, pumping, and shotcrete, for the blast furnace. Furthermore, because the power input is not limited by the. Service property for refractory is the key effect on the life of blast furnace.
If the heat input to the furnace is limited, such leaks. Differentiated use of refractories in blastfurnace hot. All of these developments have helped result in lower iron costs, increased blast furnace campaign life and improved working conditions for operational and maintenance personnel. In a blast furnace, fuel coke, ores, and flux limestone are continuously supplied through. With todays large blast furnaces, the main trend in hotblast stoves is toward high temperature and. Pdf wear mechanism for blast furnace hearth refractory lining. Health and safety executive contents introduction 3 executive summary 3 the event 3 the cause 3 the investigation 4 lessons 4 background 8 the company 8 the plant 8 the management structure 8 the blast furnace 9 the structure of the blast furnace 9 the ironmaking process 11 no. Us5890805a method for monitoring the wear and extending the. The article presents the method of estimation of refractory lining inner profile of blast the furnace crucible and bottom of volume 1719 m3. 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.
They are also finding more applications in blast furnace linings, although this use is still rare. When choosing refractory brick used for different lining parts of blast furnace, we should follow some principles. In the steel industry, the blast furnace is a process for making molten iron by melting iron ore. The company garnered accolades for the superior performance of the lucy furnace and began to expand rapidly, pushed in large measure by the explosive growth of the steel industry. 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. 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. Blast furnace hearth, tuyere surround, bosh, lower stack. Any material expands when heated, and contracts when cooled. Blast furnaces may have the following ancillary facilities. Best blast furnace refractory for sale in rongsheng. A refractory material or refractory is a material that is resistant to decomposition by heat, pressure, or chemical attack, and retains strength and form at high temperatures. Supplying all required refractory products specifically developed to extend bf lifetime. The main refractory lining of blast furnace hearth is composed by carbon blocks that operates in. What are the main decisive viewpoints in selecting suitable linings for given technological equipment.
The significance of improving the refractory configuration, the installation methods, and the short turnaround time for the repair will be discussed. Optimization of refractory lining used in blast furnace a thesis submitted in partial fulfillment of the requirements for the award of the degree of master of technology in mechanical engineering thermal engineering by pramod kumar bhagat 2me3425 department of mechanical engineering national institute of technology rourkela odisha769008, india. Schematic diagram of blast furnace inside b control of blast furnace processing by center coke charging hot metal tuyere. Refractory lining of blast furnace a modern blast furnace bf is refractory lined to protect the furnace shell from the high temperatures and abrasive materials inside the furnace. Pdf blast furnace hearth refractory and coke ash mineral. The refractory lining of blast furnaces and modernization of their. Milestones of our blast furnace operation technologies tamura categorized our history of pigiron making into the following three periods, in an article. Blast furnace refractories blast furnace lining refactory allied.
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