Column a structural element that usually carries its primary loads in compression or tension parallel its axis. So, we have discussed little bit about the oxygen steel making process. Main environmental issues in the production of iron and steel. The name ld stands for linz and donawitz, these were the two places in austria where the process was born. Blowing oxygen through molten pig iron lowers the carbon content of the alloy and changes it into lowcarbon steel. Slag carry over is an unwanted practice which cannot be completely prevented during tapping of liquid steel from primary steel making furnace. What is the difference between primary and secondary tmt. Energy use in the steel industry the steel industry actively manages the use of energy. Because the primary ghg emitted by the iron and steel industry is carbon dioxide co 2, the control technologies and measures presented in this document focus on this pollutant. The major development of the clu process was the idea to use superheated steam as the diluting gas instead of argon ar gas which is used in the aod process. Offgas compos ition, pressure and argon flow rate d uring ulc pro duction in vd. Column base usually a thick plate at the bottom of a column through which anchor bolts mechanically connect the column and transfer forces to the. This problem can be solved to some extent using anticorrosion applications.
Even though equipment is improved and higher production rates can be achieved, the processes. Iron ore iron is a moderately reactive metal which joins readily with nonmetals such as oxygen. In this simulation you will play the role of plant metallurgist in charge of secondary steelmaking operations. Pig iron is divided into steelmaking pig iron, which is intended for further processing to steel by various refining processes, and foundry pig iron, from which cast iron is produced by remelting.
Steel is primarily produced using one of two methods. Steelmaking and refining introduction to chemistry. This module introduces the learner to the critical step of refining the chemistry of the steel in order to impart the desired properties required for the grade of steel being produced. It begins by tracing the history of iron and steel production, right from the earlier days to today s world of oxygen steelmaking, electric steelmaking, secondary steelmaking and continuous casting. Advantages and disadvantages of structural steel structures. Secondary steel making processes linkedin slideshare. Steel production american iron and steel institute. Linzaus tria, october 20 06 secondary steel making session pa per no. This book is primarily focused to meet the needs of undergraduate metallurgical students and candidates for associate membership examinations of professional bodies amiim, amie. Scrap steel is charged to begin a cycle, and alloying agents and slag materials are added for refining. Steel making is the method of processing and producing steel from iron ore and scrap. In a spray type cooler the coke oven gas is cooled by direct contact with a recirculated. These reactions involve numerous different solids, liquids, and gases, and are carried out using many diverse types of furnaces. Today, steel making uses electricity and other means for providing the heat.
Low levels of s and p in the metal are acceptable to the customer but the levels of c. At high temperatures, oxygen is blown through the metal, which reduces the carbon content to between 01. The largest commercial steelmaking enterprise, nippon steel in japan, was responsible for producing 26 million tons in 1987, and 11. It involves processing iron ore to produce iron sinter or pellets, and then melting these in a blast furnace bf with coke to make pig iron. Ld process is a refining process which is carried out in a ld vesselor ld converterbof. The lime combines with the silicates, aluminum oxides, magnesium oxides, manganese oxides and ferrites to form. This process is also called as basic oxygen process. Zealand are both unusual, making the overall process almost unique. The effects of other elements can be estimated by equating them to an additional amount of carbon. The production of primary steel is more energy intensive than the production of. The reference may be from a previous version of the section and no longer cited. Instead it is found as an ore, in which iron is chemically combined with oxygen or other nonmetals.
Primary steelmaking principles in principle, steelmaking is a melting, purifying, and alloying process carried out at approximately 1,600 c 2,900 f in molten conditions. It also uses liquid steel from an electric arc furnace eaf or any other similar primary steel making 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. The process was originally used solely for making high quality steel, such as those used for machine tools and spring steel, as it gave more precise control over the composition. In this activity, you can find out more about two different methods of making iron that are often used in industry. The first blast furnaces appeared in the 14th century and produced one ton per day.
The majority of european steel 60% is made via the primary route. Energy conservation in steelmaking is crucial to ensure the. This is processed in a basic oxygen furnace bof to create steel. In primary forming, the steel that is cast is then formed into various shapes, often by hot rolling, a process that eliminates cast defects and achieves the required shape and surface quality.
Fact sheet energy use in the steel industry worldsteel. Hot rolled products are divided into flat products, long products, seamless tubes, and specialty products. Students learn about iron and steel through discussions, demonstrations and suggested optional activities. Metallurgical coal or coking coal is a vital ingredient in the steel making process. Therefore, there is a continuing demand for primary steel. To develop computational and mathematical abilities to be applied for process design and control. Pdf introduction to the production of clean steel researchgate. Basic oxygen steelmaking is a method of primary steelmaking in which carbonrich molten pig iron the iron created in the blast furnace is made into steel. The rest of europes steel comes from the secondary route. Directly reduced iron directly reduced iron is a product of iron steel direct reduction from ores in the solid. All countries with annual production of crude steel at least 2 million metric tons are listed. Iron ore, as mined, is a combination of iron with oxygen and various other.
At the same ime, alloying t materials are added to the furnace to achieve the required chemical composition of the final product. The next step targets on alloying it by adding various elements like manganese, chromium. Iron and steel video a short video clip illustrating the process of iron and steel making that can be viewed online by students or downloaded for showing in class. Microstructure through heat treatment and deformation processing so, this is. The process is known as basic because fluxes of burnt lime or. The physicochemical fundamental concepts of chemical equilibrium, activitycomposition relationships, and. The secondary steelmaking module is part of the steel manufacturing course.
Steel making slag produced in the primary section and. Steel furnace slag is produced in a bof basic oxygen furnace or an eaf electric arc furnace. Steel making carbon equivalent to a good approximation, the weldability of steel can be estimated from its chemical composition. In principle, steelmaking is a melting, purifying, and alloying process carried out at approximately 1600 c 2900 f in. Proving to be harder and stronger than bronze, which had previously been the most widely used metal, iron began to displace bronze in weaponry and tools. The most significant alloying element effecting weldability is carbon. This is a list of countries by steel production in 1967, 1980, 1990, 2000 and from 2007 to 2018, based on data provided by the world steel association. Primary cooler the first step in the treatment of raw coke oven gas is to cool it to remove water vapor and so greatly reduce its volume.
The cast steel can then be forged or rolled in successive steps to produce anyone of the many required shapes. Corus the chemistry of steelmaking notes for teachers. Indeed, many of the reactions interfere with one another. In essence, all primary iron and steel production processes are based on the same chemical reactions. In the bar chart at the top of the page, you can see how the composition of the steel that is ready for casting compares with the metal that the customer ordered. Following is a description of making steel using refined coal as the heat source. The refining of iron to make steel is where the carbon content of hot metal is lowered, usually to less than 1 % by an oxidation process in a steelmaking furnace. Cycles, or heats, range from about 112 to 5 hours to produce carbon steel and from 5 to 10 hours or more to produce alloy steel. Various chemical reactions are initiated, either in sequence or simultaneously, in order to arrive at specified chemical compositions and temperatures. The blast furnace is the first step in producing steel from iron oxides. Steel is produced using primary or secondary methods, as shown in figure 2. It has high maintenance costs as it has to be painted to make it corrosionresistant. This authoritative account covers the entire spectrum from iron ore to finished steel.
Primary steel is acquired from a steel making process known as bof, also know as converter process. Integrated steelmaking operations fall into three main phases. Direct reduction scrap ladle refining electric arc furnace steelmaking iron ore pellets electric arc furnace steelmaking continuous casting design by cover photo. For the following few thousand years, however, the quality of iron produced would depend as much on the. There are two basic types, the spray type cooler and the horizontal tube type. It begins by tracing the history of iron and steel production, right from the earlier days to todays world of oxygen steelmaking, electric steelmaking, secondary steelmaking and continuous casting.
Steel making by ld process slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. It focuses on removing the slugs and other unwanted materials like phosphorus, sulphur, silicon, nitrogen, and excess carbon from the raw iron. Bos basic oxygen furnace and the more modern eaf electric arc furnace methods. Bof technology is used for primary steelmaking, and ladle.
The steel industry has grown from ancient times, when a few men may have operated, periodically, a small furnace producing 10 kilograms, to the modern integrated iron and steelworks, with annual steel production of about 1 million tons. Today, however, it is also employed in making more widely used steels, including alloy and stainless grades as well as some special carbon and lowalloy steels. This is why we do not find pure iron in the earths crust. Bos methods add recycled scrap steel to the molten iron in a converter. Be able to understand basic layout of blast furnace, steelmaking shop and continuous casting process. The basic oxygen steelmaking process differs from the eaf in that it is autogenous, or selfsufficient in energy. The primary raw materials are steel scrap, direct reduced iron dri andor hot metal. The liquid steel can then be cast or formed into a variety of solid shapes via the continuous casting process. The production of steel in an eaf is a batch process. Corus the chemistry of steelmaking student worksheet 2 other methods of making iron you dont always need a blast furnace to make iron. Hot iron bof andor scrap metal eaf are the primary metals to make steel in each process.
The development of steel can be traced back 4000 years to the beginning of the iron age. However, the two main stages in the production of steel in new. You will take charge of a ladle of molten steel from the basic oxygen furnace bof, and attempt to deliver it to the appropriate caster at the specified time, composition, temperature and inclusion content cleanness. Modeling related to secondary steel making request pdf. In iron ore, iron is presents in its oxidised form. If you continue browsing the site, you agree to the use of cookies on this website. Steel making is designed to give students a strong grounding in the theory and stateoftheart practice of production of steels. Salzgitter the process shown above is illustrative only and is not designed to show the steelmaking process in detail. The difference is basically in the steel making process. Ironmaking and steelmaking metallurgical and materials. There are extensive fireproofing costs involved as steel is not fireproof.