Steelmaking is an extensive industry based on modifying the physical properties of iron to fit a wide range of applications by either adding alloying elements or removal of impurities. Basic oxygen steelmaking reactions iron and steelmaking ii. Results are measured by total time, total cost and steel composition. However, during this steelmaking reactions, oxygen concentration has been increased. May 14, 2011 the basic oxygen steelmaking process differs from the eaf in that it is autogenous, or selfsufficient in energy. The primary raw materials for the bop are 7080% liquid hot metal from the blast furnace and the balance is steel scrap. The optimal control indicator is determined via current state of converter smelting production process, and the set values of operation variable would control converter production. The origin of modern oxygen steelmaking steel times 92000, 328330 20h. The presentations describes bof steelmaking process, factors affecting lining life and bof gas collection and cleaning. The first metallurgical step is to reduce iron ore to metallic iron, a. Steelmaking plants commonly have inhouse mass balance. The furnace needs no heating because the oxygen combines very exothermically with the impurity elements, carbon, silicon, manganese and phosphorus.
Modern steelmaking abhay deo 12met012 metallurgy,giet gunupur 2. The basic oxygen steelmaking module is part of the steel manufacturing course. A description of the first basic oxygen steel plant in the rocky mountain area, this article also includes operating data since startup on the 11th of july. Iron contains impurities in the form of silicon, phosphorus, sulfur, and manganese. Deoxidation of the steel is accomplished by the addition of silicon. 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. Rhamdhani swinburne university of technology, hawthorn, vic 3122 australia key words. Danieli linz oxygen converter steelmaking plants danieli. May 10, 2018 found in every corner of the planet, steel has come to be one of our most used materials for building a sturdy product. Basic oxygen furnace route steelmaking costs 2020 conversion costs for bof steelmaking. How steel is made using the basic oxygen steelmaking process.
Killed steel carbon and oxygen react in the steelmaking process to form a gas. Ironmaking and steelmaking bof basic oxygen furnace dlt danieli linz technology is the center for competence of converter oxygen steelmaking, covering the complete range of products downstream of the blast furnace and upstream from secondary metallurgy, in. 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 supersonic velocity. Metallurgy of iron, steelmaking 1 gmelindurrer, 4th. Basic oxygen steelmaking simulation steeluniversity. The basic oxygen steelmaking vessel is an 11mhigh cauldron which converts iron into steel by pumping oxygen through the molten metal at twice the speed of sound, removing unwanted carbon. And also, depending on type of products, the liquid steel should contain certain amount of alloy elements.
The oxygen steelmaking process is a generic name given to those processes in which gaseous oxygen is used as the primary agent for autothermic generation of heat as a result of the oxidation of dissolved impurities like carbon, silicon, manganese and phosphorus and to a. 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. 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. The basic oxygen steelmaking bos process consortium. Dynamic operation optimization has been utilized to realize optimal control problem for converter. Model development for refining rates in oxygen steelmaking.
Numerical simulation of slag foaming with reaction. Products ironmaking and steelmaking bof basic oxygen. So this is really the prototype of oxygen steelmaking. Modelbased closedloop control of the basic oxygen steelmaking process will give an opportunity to increase process operation performance. After the blow has continued for about 20 minutes, the metal is sampled. Basic oxygen furnace based steelmaking processes and. Comparative assessment of ld converter and electric arc furnace. May 22, 2016 the presentations describes bof steelmaking process, factors affecting lining life and bof gas collection and cleaning. Feb 25, 2016 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. Content introduction types of steel classification of carbon steel process of steelmaking basic oxygen furnace dri based steel making bessemer process open hearth furnace production of steel modern steelmaking process.
Kinetics of decarburization reaction in oxygen steelmaking. Development of a comprehensive model for oxygen steelmaking. The word basic refers to the ph of the refractories lining the ladle interior, which are normally composed of calcium oxide or magnesium oxide. Basic oxygen process bop, a steelmaking method in which pure oxygen is blown into a bath of molten blastfurnace iron and scrap. Abstract removal of impurity elements from hot metal is essential in basic oxygen steelmaking. The scrap is used mainly to lower the furnace temperature.
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. A novel process control model for basic oxygen furnace bof steelmaking is proposed based on metallurgy mechanism, with lower contents of carbon, manganese, silicon, and lower temperature in semi. Steel is made by the bessemer, siemens open hearth, basic oxygen furnace, electric arc, electric highfrequency and crucible processes. However, blowing oxygen at high speed is sometimes not effectively. 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. 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. Towards modelbased closedloop control of the basic oxygen. The basic oxygen steelmaking bos process consortium steel.
Dephosphorization during the latter part of the basic oxygen steelmaking process is very important because the conditions are favorable compared to other processes within primary and secondary steelmaking. The development of a process charge expert system for a. How to low cost ce materi national chung hsing university 105 11. The aim of the process is to remove carbon and several minor elements from iron melt by blowing oxygen on top of the melt. 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.
Dephosphorization strategies and modelling in oxygen steelmaking. Before casting, this oxygen could be lowered again. The oxygen steelmaking process is a generic name given to those processes in which gaseous oxygen is used as the primary agent for autothermic generation of heat as a result of the oxidation of dissolved impurities like carbon, silicon, manganese and phosphorus and to a limited extent the. Recycling and reuse of basic oxygen furnace bof basic oxygen process bop in steelmaking slags continued based on previous research conducted by mtu, it is believed that steelmaking slag can be processed into highiron and non iron fractions. Cleveland receives basic oxygen steelmaking springerlink. The process occurs in a furnace which is a specially designed steel vessel that may be rotated through 360 in a vertical plane.
The basic oxygen steel bos making process this can be described via the following steps. 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 supersonic. Jamie shorta, chris barnesa, dr mark evansb, dr roger grosvenorc, paul prickettc. Modelling of basic oxygen steel making process has significant utility as productivity and lining life of basic oxygen steelmaking bos is highly dependable upon mass, momentum, energy. Plant and equipment, metallurgical processes, chemistry, raw materials, products and byproducts. To put it simply, basic oxygen steelmaking is a means of producing steel by using oxygen.
The aim of this simulation convert approximately 250 tonnes of hot metal and scrap into steel. The basic oxygen steelmaking process differs from the eaf in that it is autogenous, or selfsufficient in energy. Pdf desphosphorization in ironmaking and oxygen steelmaking. As oxygen is injected into a basic oxygen furnace, carbon, silicon,manganese and iron. Despite the advances in steelmaking technology,9 which have taken place since bessemers day, slopping remains. These are charged into the basic oxygen furnace bof vessel. And by blowing oxygen gas with the lance at very high speed, steelmaking literally could be accelerated, very rapidly. Basic oxygen steelmaking bos, bop, bof, and osm, also known as linzdonawitz steelmaking or the oxygen converter process is a method of primary steelmaking in which carbonrich molten pig iron is made into steel. Primary steelmaking known as linzdonawitzverfahren steelmaking 28. Below is a picture that displays a simplified version of the bos process.
Modelling of basic oxygen steel making process has significant utility as productivity and lining life of basic oxygen steelmaking bos is highly dependable upon mass, momentum, energy transfer and rigorous interaction among metal, slag and gaseous phases. Ironmaking and steelmaking bof basic oxygen furnace dlt danieli linz technology is the center for competence of converter oxygen steelmaking, covering the complete range of products downstream of the blast furnace and upstream from secondary metallurgy, in complete symmetry with danieli corus ijmuiden. Basically, once when the steelmaking technology is developed, lance was first lowered from top position. The bos process uses pure oxygen, injected by a lance, for refining. Top oxygen blowing, widely referred to as the ld converter process, and steelmaking in the electric arc furnace, are nowadays the two most widely used. Steel is run out of the taphole into a ladle, separating it from the lighter slag, which is later emptied as waste. Thomas4 optical microscopy, total oxygen measurements and slime tests have been conducted to quantify. It is therefore critical to maintain a slag composition that improves the phosphorus removal. In many ways the techniques of primary steel making were neglected in favour of secondary processes but with these developments logistics and the.
A global model of oxygen steelmaking including the kinetics of scrap melting, flux dissolution, slag chemistry, temperature profile of the system, formation and residence of metal droplets in the emulsion, kinetics of. The process is known as basic because fluxes of burnt lime or. The bos process is now complete and the furnace can be tapped. Metallurgy of iron, steelmaking 1 gmelindurrer, 4th edition, volume 7a,7b, springer verlag 1984. Although oxygen steelmaking is a wellknown process there are a lot of current challenges for the operating engineer. By using control algorithms that interact with thermodynamical and physical models capable of making realtime predictions of the effects of control actions, the time delays in order to wait for process response will be eliminated. Relationship between various operating variables, current temperature, and carbon content is constructed through. A basic oxygen furnace is a reactor in which oxygen is blown through molten pig iron that is heated to approximately 1,600. Oxygen furnace bof to create liquid steel, solidifying the liquid steel via continuous casting, and finally sending the semifinished casts to various finishing refinements. Kinetics of decarburization reaction in oxygen steelmaking process neslihan dogan, geoffrey a. Steel cost modelling notes the steel costing model the economic model shown above is prepared only to shown how liquid steel cost can be calculated through a simple cost benchmarking type approach.
If the oxygen available for this reaction is not removed deoxidized prior to casting, the gaseous products continue to evolve during solidification. The second principle is that discovered by hess 1840. Exenberger voestalpine stahl, linzlaustria equilibrium shares of oxygenelectric steelmaking considering charge supply 51. The predicted total costing shown is not meant to represent an actual cost for any real steel company. The injection of powdered materials, capable of reacting rapidly with a metallic bath has long been considered, and for. Basic oxygen furnace based steelmaking processes and cleanliness control at baosteel l. Primary steelmaking continuous improvements and high performance in ld steelmaking at voestalpine stahl gmbh, linz 41 h. Today the task and aim of the basic oxygen steelmaking bos technology is to supply molten steel produced from hot metal, scrap, flux and other. Development of a comprehensive model for oxygen steelmaking neslihan dogan, geoffrey a. The oxygen initiates a series of intensively exothermic heatreleasing reactions, including the oxidation of such impurities as carbon, silicon, phosphorus, and. Basic oxygen steelmaking reactions iron and steelmaking. F converter life, reliability and costs are vital to the smooth operations of steel plants worldwide. Comprehensive thermodynamic model of basic oxygen steel making pro.
Found in every corner of the planet, steel has come to be one of our most used materials for building a sturdy product. Towards modelbased closedloop control of the basic. Its composition at this stage is shown in bar chart 3. The main functions of the basic oxygen furnace bof are to decarburize and remove phosphorus from the hot metal, and to optimize the.
Basic oxygen steelmaking also known as linzdonawitzsteelmaking or the oxygen converter. Topic welding industry metallurgy basic oxygen steelmaking. Two types of furnaces that create steel are the basic oxygen furnace and the electric arc furnace, each of which have their own set of pros and cons. Mass balances provide a fundamental approach for analysing the oxygen steelmaking process. Trentini, b and allard, m 1959 steelmaking by injection of oxygen and lime powder irsido.
Blowing oxygen through molten pig iron lowers the carbon content of the alloy and changes it into lowcarbon steel. After charging, the furnace is blown by blasting oxygen through a lance that is lowered into the molten metal. Understanding dephosphorization in basic oxygen furnaces mdpi. This is achieved by blowing oxygen into the melt to cause a decarburization in the melt which lowers the carbon content to between 0. This module introduces the learner to the operation of the basic oxygen steelmaking furnace for the transformation of molten iron to steel. The vessels are lined with heat resistant refractory materials eg. Sixstory buildings are needed to house the basic oxygen furnace bof vessels to accommodate the. Fundamentals of iron and steelmaking 39 equal to its heat of formation, but of opposite sign. In both the acid bessemer and basic bessemer or thomas processes molten pig iron is refined by blowing air through it in an eggshaped vessel, known as a converter, of 1525 tonnes capacity. In primary metallurgy, the converter process is an important stage in the production of steel from iron ore. Steelmaking by injection of oxygen and lime powder irsido. Basic oxygen steelmaking how is basic oxygen steelmaking. Thermodynamics of phosphorus and sulphur removal during basic. 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.
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