C 417, 2012 abstract the target in this thesis was to study selected special measurements in a basic oxygen furnace bof and develop a model to predict the steel temperature at the end of the oxygen blow. Basic oxygen steelmaking bos makes steel from blast furnace iron and up to 20% of scrap metal. It is also known as the linzdonawitz steelmaking process or the oxygen conversion process. Steel is run out of the taphole into a ladle, separating it from the lighter slag, which is later emptied as waste. Understanding dephosphorization in basic oxygen furnaces mdpi. Revised standards for basic oxygen process furnaces. Lancing is the precise injection of oxygen to the point where it is most needed. Commonly known as bof, this type of furnace relies on pure oxygen, rather than air, to convert iron into steel. The resulting silica, iron oxide and maganese oxide react with fluxes charged into the. The distribution of these plants within the united states is shown in figure 32.
Argon oxygen decarburization furnace steel slag aod duration. The diagram shows oxygen being blown into the furnace or bos vessel through a. The bos process is now complete and the furnace can be tapped. More than half the worlds steel is produced in the basic oxygen process bop, which uses pure oxygen to convert a charge of liquid blastfurnace iron and scrap into steel. A basic oxygen furnace is a reactor in which oxygen is blown through molten pig iron that is heated to approximately 1,600. High zinc content in solid wastes from basic oxygen furnace steelmaking offgas cleaning systems is one of the main barriers for source recycling of the solid wastes back into ironmaking and steelmaking process. The oxygen ratio in this experiment was increased under the condition of constant bosh gas volume per unit time. Water is separated into and oxygen by a solarpowereel water.
How steel is made using the basic oxygen steelmaking process. Slopping is related to the process of slag formation in basicoxygen steelmaking. At the end of the basic oxygen steelmaking process, described in chapter 5. The basic oxygen steel bos making process this can be described via the following steps. Basic oxygen process bop, a steelmaking method in which pure oxygen is blown into a bath of molten blast furnace iron and scrap. A typical topblown basic oxygen furnace is a vertical cylindrical vessel with a closed bottom and an open upper cone through which a watercooled oxygen lance can be raised and lowered. Primary steelmaking known as linzdonawitzverfahren steelmaking 28. Energy and exergy analysis of a basic oxygen furnace. In india and in most industrial countries, the use of bof slag as a road ballast and land filler has had a very long history. Theauthors haveproposedthe oxygenblast furnace process. The basic oxygen furnace process uses 25 to 35 percent old steel to make. Blowing oxygen through molten pig iron lowers the carbon content of the alloy and changes it into steel.
Basic oxygen furnace process using pyroptix st camera from enertechnix for more information, please visit. These wastes are generally landfilled or dumped to the sea. In oxygen wear was significantly reduced during the initial. There are three principal categories of oxygen furnaces that are utilized. Most new eaf shops now aim for taptotap times of between 5060 minutes. Basic operating weight article about basic operating weight.
Basic oxygen furnace latest breaking news, pictures, videos, and special reports from the economic times. A basic oxygen furnace bof is the machinery used for purification of pig iron by oxidizing impurities into slag and converting the rest into molten steel with an injection of oxygen. This submission will address topics 1, 2, 4 and 10 in the ostps rfi. At the end of the basic oxygen steelmaking process, described in chapter 5, blast furnace gases contain 30% co 2, and the concentration in the overall flue gas stream from an integrated steel mill is 15%. Related reactions and technics are also introduced. Basic oxygen steelmaking also known as linzdonawitzsteelmaking or the oxygen converter process is a method of primary steelmaking in which carbon rich. Basic oxygen furnace process iron and steelmaking ii.
Geotechnical properties of fresh and aged basic oxygen furnace steel slag article pdf available in journal of materials in civil engineering 2712. Furnace oxidation wet dry process summary thermal oxidation is a reactive growth processes that combined both transportation and surface reaction. Considering the priceperformance optimization, our refractory experts gives customized engineering, design and supervisory services to our customers. The steel produced is chemically tested and may be further modified by the addition of alloys. This course handles the steel making process which is converting the hot metal formed in the ironmaking process into steel. Overlooking no dissociation during the quenching of a gas sample, and recalculating no 2 to no, the data points would reflect the concentrations of no in the furnace atmosphere for enormous sets of partial pressures for nitrogen and oxygen it must be remembered that during the measurement periods, the furnace was exposed to heavy leakage.
Basic oxygen furnace bof steel making or basic oxygen furnace steelmaking bos or linzdonawitzverfahren steelmaking or the oxygen converter process is a method in which both molten pig iron and steel scrap are converted into steel with the oxidizing action of oxygen blown into the melt under a basic slag. Blowing oxygen through molten pig iron lowers the carbon content of the alloy and changes it into lowcarbon steel. Below is a picture that displays a simplified version of the bos process. Basic oxygen furnace based steelmaking processes and. N scale steel mill basic oxygen furnace bof uss edgar thomson works, duration. The oxygen steelmaking process converts the molten iron from the blast furnace with up to 30% steel scrap into refined steel. High purity oxygen is blown through the molten bath to lower carbon, silicon, manganese, and phosphorous content of the iron, while various fluxes are used to reduce the sulfur and phosphorous levels. Oxygen flow commonly reaches 200280 ft3mint 68 m3mint. Basic oxygen steelmaking is a method of primary steelmaking in which carbonrich molten pig iron is converted into steel. The basic oxygen furnace bof is a refractorylined, tiltable converter into which a vertically movable, watercooled lance is inserted to blow oxygen through nozzles at. Iron contains impurities in the form of silicon, phosphorus, sulfur, and manganese. The results of tests under a dry air atmosphere fig. During the oxygen blow the lance is lowered into the mouth of the upright furnace. Astm toc section 00 index section 01 iron and steel products volume 01.
A brief discussion of the process is included in the following paragraphs. Oxygen lancing oxygen lancing is used in similar situations to enrichment however is typically associated with more severe or complex conditions. Its composition at this stage is shown in bar chart 3. This is a recollection of how i kitbashed a basic oxygen furnace bof facility in ho scale back in 1997, starting with a pair of walthers electric furnace building kits and adding a large rectangular building in behind them. Modern furnaces will take a charge of up to 350 tonnes and convert it into steel in less than 40 minutes. Process characteristics commercialscale oxygen furnace. Basic oxygen furnace based steelmaking processes and cleanliness control at baosteel l. As the basic oxygen furnace shell is exposed to severe hightemperature conditions during use, its material experiences gradual degradation leading to thermal deformation and cracking that.
Thanks to the possibility to use slag builders and oxygen, during the electric arc furnace process is possible to reach low phosphorous and low controlled carbon content at the end of the refining period. Basic oxygen furnace bof is a steel making furnace, in which molten pig iron and steel scrap convert into steel due to oxidizing action of oxygen blown into the melt under a basic slag. Box 4300, fi90014 university of oulu, finland acta univ. Process and the fuchs shaft fur nace can achieve even lower cycle times. The basic oxygen steelmaking process is the uks major method for making steel. Basic oxygen steelmaking bos is a primary steelmaking method in which the highcarbon molten pig iron is converted to steel. Charge materials tially charged 100% scrap to the furnace. Introduction the purpose of the basic oxygen steelmaking bos process is to refine the hot metal produced in the blast furnace into raw liquid steel, which may be subsequently refined in the secondary steelmaking shop. The basic oxygen furnace the basic oxygen steelmaking process is the uks major method for making steel. The initial growth of silicon dioxide is a surface reaction only. These times are rapidly approaching those for basic oxygen furnace operations used in integrated steel mills. The experiments were performed in an inert argon atmosphere.
The production of steel by the basic oxygen process proceeds in distinct steps or operations. The purpose of the basic oxygen steelmaking bos process is to refine the hot metal produced in the blast furnace into raw liquid steel, which may be subsequently refined in the secondary steelmaking shop. Bulk oxygen displacement on a basis of per mole of deoxidant added, carbon would remove more oxygen than what aluminium could do, due to the lower molecular mass fraction of oxygen in the reaction product carbon monoxide co, compared to that in alumina al2o3. Basic oxygen furnace bof slag is a major waste product generated during the steelmaking process. Oxygen of 95% purity is used in welding, cutting and blast furnace. This being a low end use, a study was conducted to examine the possibility of converting the slag into a hydraulic binder. The iron ore concentrate is now mixed and ready for the pelletizing process. Dmitri kopeliovich basic oxygen furnace bof is a steel making furnace, in which molten pig iron and steel scrap convert into steel due to oxidizing action of oxygen blown into the melt under a basic slag the basic oxygen process basic oxygen furnace, basic oxygen steelmaking, basic oxygen converter is the most powerful and effective steel making method. Hot metal pretreatment to decrease some of the impurities, and basic oxygen furnace bof process to reach the required composition will be treated in detail. The main functions of the basic oxygen furnace bof are to decarburize and remove phosphorus from the hot. Pdf the basic oxygen furnace bof process is an exceedingly fast refining process needing a good dynamic model for better. Pure oxygen is then blasted into the furnace at supersonic speeds via an oxygen lance that is lowered from the top. 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.
Hot metal pretreatment before entry into oxygen steelmaking is employed in japan. Primary deoxidation of basic oxygen furnace steel by. The second type of furnace is the bottom blown qbopf. Laboratory characteristics and prediction calculations article pdf available in international journal of mineral. The basic oxygen process basic oxygen furnace, basic oxygen. Pdf geotechnical properties of fresh and aged basic. Oxygen furnace bof to create liquid steel, solidifying the liquid steel via continuous casting, and finally sending the semifinished casts to various finishing refinements. In this case, the converter gas, which is generated by oxygen blowing process, is cleaned. Various purity of oxygen is used in the steelmaking industry. Recycling of basic oxygen furnace steelmaking dust by in. Using oxygen reaction as electricity saving in electric. My original intent was to suggest the presence of a bof mill, not to build a faithful replication of a prototype i.
Phenomena of oxygen enrichment in a blast furnace process. There are six steps in the production of steel using the basic oxygen process. Basic oxygen furnace model railroader magazine model. Basic oxygen furnace bof the basic oxygen furnace process uses 25 to 35 percent old steel to make new steel. For the vast majority of the airplanes we fly, the range between v. As oxygen is injected into a basic oxygen furnace, carbon, silicon,manganese and iron are oxidized a more complete description of b. During each stage of the process the furnace is turned in different directions. Basic oxygen furnace bof is a steel making furnace, in. The vessels are lined with heat resistant refractory materials eg. Utilization of basic oxygen furnace bof slag in the. This is in the same range as for coalfired power plant, and the capture options introduced above for power generation are equally applicable for steel production, namely. The water i cell, which generaeselectricity, h solarpowered e c o and y sthe er the e e o process, h e m which a l operates like a giant rechargeable b a has the e potential to deliver commercial, operational and environmen benefits for electricity. The process is known as basic due to the chemical nature of the refractoriescalcium oxide and magnesium oxidethat line the vessel to withstand the.
This is shown clearly in the accompanying diagrams. In this furnace oxygen is introduced into the vessel through tuyeres openings in the furnace bottom. Basic oxygen process bop, a steelmaking method in which pure oxygen is blown. Overlimit zinc loadings to blast furnaces might damage blast furnace refractory materials, and hence shorten blast furnace campaign life. The process occurs in a furnace which is a specially designed steel vessel that may be rotated through 360 in a vertical plane. Along with the liquid iron that was produced in the blast furnace, recycled scrap steel is also added to the oxygen furnace. Suggest a mechanism for the stage ii process in the reaction of f with concentrated hbraq, including curly arrows to denote movement of electrons, and all charges. An investigation was made on the oxygen enrichment to blowing gas up to 40% by using an experimental blast furnace. It is the primary method used for steel production worldwide. The vessel is lined with a refractory such as magnesite and is mounted on trunnions so that. Binder must be used for the iron ore pellets production. The chemistry of steelmaking the basic oxygen furnace. Basic oxygen steelmaking bos, bop, bof, or osm, also known as linzdonawitzsteelmaking or the oxygen converter process is a method of primary steelmaking in which carbonrich molten pig iron is made into steel. First were going to present the company arcelormittal with whom we worked with on this project, then in a first part we will detail the steps of steel making, in a second part present the energy analysis of the process and then finish with a third part on the exergy.
After the sio2 thickness begins to build up, the arriving oxygen molecules are diffused through the. Other articles where basic oxygen furnace is discussed. Basic oxygen process an overview sciencedirect topics. How steel is made using the basic oxygen steelmaking. A basic oxygen furnace is a pearshaped structure with a closed bottom and an open top that works to process steel. Top blown process bop in the top blown process a water cooled oxygen lance is lowered from the top of the furnace and blows oxygen at supersonic speed into the melt. Basic oxygen steelmaking article about basic oxygen.
After the blow has continued for about 20 minutes, the metal is sampled. The oxygen steelmaking process is one of the most common and efficient steel production methods. Typically close to the furnace in an underport or throughport location or even through a target wall. Pyrite ash wastes can be utilized in the iron production industry as a blast furnace feed to prevent environmental pollution and evaluate these wastes, but it is necessary to develop a process for agglomerating it into pellets. Basic oxygen furnace blogs, comments and archive news on.
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