Blowing oxygen through molten pig iron lowers the carbon content of the alloy and changes it into low. The ld converter linzdonawitz converter has a refractory lining often consisting of dolomite. The name ld stands for linz and donawitz, these were the two places in austria where the. Development of the ld process the story of the ld process a series of experiments began on june 3, 1949 on the former voest site, using a 2tonne experimental converter. It can be categorized as carbon steel slag and stainless steel slag according to the type of steel, and as pretreatment slag, linzdonawitz ld converter slag, electrical arc furnace slag eafs, ladle refining slag and casting residue according to the steelmaking process meng and liu, 2000. Converter steelmaking converter steelmaking is the main step in orebased steel production using blast furnace hot. Ldconvertor atibir industries company limited steel. Pig iron is divided into steelmaking pig iron, which is intended for further processing to. 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.
An overview of use of linzdonawitz ld steel slag in. Steelmaking technologies contributing to steel industries. Steelmaking slag processing technology the ironsteel slag processing flow is schematically shown in fig. Krieger university of mining, metallurgy and materials, leobenlaustria keynote lecture 2 mastering the heat in the feco converter. Optimisation of the bottom stirring praxis in a ldlbe converter jose aguirre castillo the ldprocess, called after the cities linz and donawitz, is used to convert pig iron into crude steel by blowing oxygen on top of the pig iron. The converter process was developed in the middle of the nineteenth century using bottomblown air for oxidation. Tata steel has over the years, undertaken extensive research in. Residence times of the droplets are strongly dependent on the decarburization rate, the co bubbles giving a. Donawitz ld converter with respect to blowing time. The earliest known production of steel are pieces of ironware excavated from an. Jun 21, 2016 the name ld converter came after the name of the two austrian towns linz and donawitz. The importance of droplet generation rate, droplet size, and its residence time in the slagmetal emulsion on the overall reaction kinetics has become evident in recent times. Converter carbon steelmaking solutions primetals technologies.
D converter has a basic lining of magnesite bricks permanent lining and dolomite bricks working lining. Converter carbon steelmaking boost your competitive edge with fullline solutions from the process inventor the demands placed on product quality, plant productivity and availability are on the rise. It can be categorized as carbon steel slag and stainless steel slag according to the type of steel, and as pretreatment slag, linzdonawitz ld converter slag, electrical arc furnace slag eafs, ladle refining slag and casting residue according to the steelmaking process. Bop is essentially an oxidising refining process in which high carbon hot. Since the beginning, scrap has been charged as a cooling agent and an additional iron. At high temperatures, oxygen is blown through the metal, which reduces the carbon content to between 01. The steelmaking process belongs to very complicated metallurgical processes. The yield of ironsteel slag is about 300 kgtp per ton of pig iron for blast furnace slag and about 100150 kgts per ton of molten steel for steelmaking slag. The name ld stands for linz and donawitz, these were the two places in austria where the process was born. Slagmetal emulsion plays an important role in the oxidation kinetics of metalloids in oxygen steelmaking. The bos method adds recycled scrap steel to the molten iron in a converter. Dec 29, 2012 it is a modified bessemer process, steel is produced in a solid bottom converter by injection of oxygen into the molten iron bath from a water cooled lance inserted through the converter mouth. Steelmaking slag is subjected to the following four processes.
Ld converter was very large, in period 20032010 it was on average not lower than 10 %. Chemical, mineralogical, and morphological properties of. A ldlbe converter, lance bubbling equilibrium, also stirs the melt trough a bottom stirring system. Thermodynamic and kinetic basics in the converter process. Basic oxygen steelmaking bos is the process of making steel by blowing pure o2 in a liquid metal bath contained in a vessel which is known as basic oxygen furnace bof, ld converter, or simply converter. In germany, ld steelmaking accounts for around 75 % of production, while the electric arc furnace is used for 25 %. Nov 14, 2016 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. The basic automation systems level 1 for converters. Pdf l 11 converter steelmaking abdul aziz academia. Modelling of basic oxygen steel making process has significant utility as productivity and lining life of basic oxygen steelmaking bos is highly dependable. Today about 80 percent of the steel in germany is produced using this method. As a result, some converters recorded a steam generation rate as high as 90 kgt crude. In hisarna ironmaking process, iron ore is processed almost directly into liquid iron or hot metal. Evolution of process control in 50 years of oxygen steelmaking 19 r.
Because of high production costs, which are closely tied to the. Basic oxygen steelmaking bos, bop, bof, and 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. Steel making is mainly concerned with the removal of these impurities. Profile of a blast furnace and its dimensions are adapted to technology of process, see figure. In addition, these two models can be regarded as the first step for a future more indepth modeling work of the post combustion. Without the necessity of this preparatory step, the hisarna process. Moreover, the post combustion phenomena in a bof or ld linzdonawitz process as well as an aod argon oxygen decarburization process were studied focusing on the decarburization stage. Hybrid process for steelmaking of scrap and hot metal another particular furnace design comes from the interest in enlarging the flexibility in raw materials, particularly hot metal. Introduction the oxygen converter process ld bof and its derivatives is the main method of carbon and low alloy steelmaking, annual production approaching to 60% of total crude steel production over 1 gton 2005. Other articles where linzdonawitz process is discussed.
Converter carbon steelmaking primetals technologies. Optimisation of the bottom stirring praxis in a ldlbe. Blowing oxygen through molten pig iron lowers the carbon content of the alloy and changes it into lowcarbon steel. 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. Media in category ld converter the following 20 files are in this category, out of 20 total. Optimisation of the bottom stirring praxis in a ld lbe converter jose aguirre castillo the ld process, called after the cities linz and donawitz, is used to convert pig iron into crude steel by blowing oxygen on top of the pig iron. According to subjective literature concerning electricarc furnace 1. Experiences in physicochemical modelling of oxygen. The software for the static control of the ld steelmaking process.
In steelmaking, impurities such as nitrogen, silicon, phosphorus, sulfur and excess carbon are removed from the raw iron, and alloying elements such as manganese, nickel, chromium and vanadium are added to produce different grades of steel. Gases can exit the converter through an opening at the. 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. Chemistry of steelmaking by basic oxygen furnace ispatguru. The bottom cylindrical part of the profile is called a. However, if one goes back as far as the middle of the 19th century, one finds that henry bessemer, the englishman who developed the air refining process, what we now know as the. About 70% of steel is nowadays produced via different variants of basic oxygen converters.
This course handles the steel making process which is converting the hot metal formed in the ironmaking process into steel. Since the early 1950s, oxygen steelmaking in a linzdonawitz oxygen steelmaking process ld converter has been the dominant method of crude steel production. The process is based around a type of blast furnace called a cyclone converter furnace, which makes it possible to skip the process of manufacturing pig iron pellets that is necessary for the basic oxygen steelmaking process. The basic oxygen converter or ld converter is a refined. Oxidation is carried out with high purity oxygen gas which is blown in the bof. Converter steelmaking converter steelmaking is the main step in orebased steel production using blast furnace hot metal and steel scrap as basic raw materials. This model also contributes towards the prediction of sloping phenomenon taken place during basic oxygen steel making process. Dissolution of scrap in hot metal under linzdonawitz ld. Steelmaking is the process of producing steel from iron ore andor scrap.
The process is also called basic oxygen steelmaking. 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. Ilrocess, basie essenrer peeress iilolnas process, duplex process acil bessemer followed by basic open hearth electric process, x\,fn feelmaking pl oeesses ld, rotor, kallo, etc. The mineralogical and morphological properties of bof and electricarcfurnaceladle eafl. Bof, and osm, also known as linzdonawitzverfahren steelmaking or the oxygen converter process is a method of. In steelmaking, impurities such as nitrogen, silicon, phosphorus, sulfur and excess carbon most important impurity are removed from the sourced iron, and alloying elements such as manganese, nickel, chromium, carbon and vanadium are added to produce different grades of steel. The purpose of this work is to develop a mathematical model to calculate the material balance. 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. On contrary, the ld converter type dephosphorization process ld nrp has been in operation at the fukuyama no. Steelmaking process was successfully lowered to an ulti. Ld bof plants from primetals technologies lead the steelmaking sector in terms of reliability and economy. Corporation will develop new steelmaking processes and contribute to meeting diverse demands. This paper provides an overview of the different types of steel slag that are generated from basicoxygenfurnace bof steelmaking, electricarcfurnace eaf steelmaking, and ladlefurnace steel refining processes. Bos basic oxygen furnace and the more modern eaf electric arc furnace methods.
Optimisation of the bottom stirring praxis in a ldlbe converter. With reference to the basic oxygen converter or ld process of steelmaking, the ways and means available to restrict oxygen level at are. A ld lbe converter, lance bubbling equilibrium, also stirs the melt trough a bottom stirring system. Primary steelmaking known as linzdonawitzverfahren steelmaking 28.
Energy balance calculations are carried out on the bof ld converter steelmaking process using the hot metal with the composition shown in table. A thesis submitted to the school of graduate studies in partial fulfilent of the requirements for the degree. Avoidance of reblow postblow stirring through bottom elements upkeep of tapholeuse of improved tap hole technology such as isojet system i to maintain sound geometry of. 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 steelmaking processes. In japan, some 40 million tons of ironsteel slag are presently produced annu. Oxygen steelmaking training dvd from the bcsa and tata steel. Related reactions and technics are also introduced. Ld process is a refining process which is carried out in a ld vesselor ld converter bof. Modeling of gas flows in steelmaking decarburization.
Basic oxygen steelmaking reactions iron and steelmaking. Dec 08, 20 chemistry of steelmaking by basic oxygen furnace. Optimisation of the bottom stirring praxis in a ld lbe. Control of slopping inbasic oxygen steelmaking by george k. For both two models bofld and aod, simulations indicated that a change of the converter temperature from 1500 to 1700 c did not influence the post combustion reaction to a large degree. Zinc in steelmaking process the dust from electricarc furnace has much higher content of elemental zinc than sludge coming from oxygen converters. The ld converters in this shop are used as a decarburization furnace in the first half of their vessel life and then as a dephosphorization furnace in the latter half. Academic materials for the economics and management of industrial systems study programme at the faculty of metallurgy and materials engineering.
Modeling of gas flows in steelmaking decarburization processes. 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. Bundesarchiv b 145 bildf0790450009, duisburg, thyssenstahlwerk, hochofen. This process is also called as basic oxygen process.
Comparative assessment of ld converter and electric arc. 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. As oxygen is passed through the molten pig iron to lower the carbon content of the alloy, the process is also called basic oxygen steelmaking. Converter process control and technological packages the fundamental basis of high quality process operations our automation systems comprise the complete range of carbon steelmaking converters ld, bof, kobm as well as stainless steelmaking technologies aod, clu and kobms. Feb 23, 2014 ld process is a refining process which is carried out in a ld vesselor ld converterbof. Ld converter is a welded construction of nonageing steel plates 8mm, the height of the vessel varies from 710m. In a conventional eaf, as hot metal charge increases, the need for oxygen injection is bigger. Converter steelmaking is the main step in orebased steel production using blast furnace hot metal and steel scrap as basic raw materials. Steel slag is a byproduct of the steelmaking and steel refining processes. Steelmaking is the process for producing steel from iron ore and scrap.