Fig 4 Concept of three stage SR process utilizing O2 and coal. The ore of the metal, in this case, galena is removed from. Most ores are the chemical compound of the metal and other elements, such as oxygen (as an oxide), sulfur (as a sulfide), or carbon and oxygen together (as a carbonate). for example: Cu 2 O + FeS → Cu 2 S + FeO. Process of roasting consists of solid-gas thermal reaction which includes oxidation, reduction, sulfation, chlorination and pyro hydrolysis. In the three-stage process, a separate gasifier is coupled with the smelting unit and the pre-reduction unit to gasify coal producing CO, H2, CH4, etc. Examples of Redox Reactions. A few envisage large scale usage of electrical heating as the source of process heat. In the second group, those processes are there which have low degree of pre-reduction and a high degree of post-combustion. In general these processes transfer partially reduced material plus some fuel (char) from the reduction unit to the melter which also performs final reduction. These SR processes utilize electricity as the source of energy and non-coking coal as reductant. Roasting is a chemical reaction in which the sulfide ore is heated with abundant oxygen and the metal sulfide is either converted to a metal oxide or a metal. This type of design allows a degree of decoupling of the reduction and melting operations, which need not be closely matched, since the process can always be brought into balance by import or export of electricity from or to the distribution grid. The reaction is synthetically very useful, due to the formation of cyclic products. The product from DR processes, direct reduced iron (DRI), is physically similar to the feedstock in form (usually iron ore lumps and/or pellets) and contains the gangue minerals present in the original ore. DRI is also known as sponge iron. All Rights Reserved © 2019, Design & Developed By: Star Web Maker. Corex process belongs to this category. Smelting reduction of iron ores to give a liquid iron product in processes other than the BF has long been recognized as a technically feasible and attractive process route and a number of process concepts have been proposed. Small scale operation – The second objective for the development of SR ironmaking process is to have an economic size of the process. The gases evolving from the liquid bath are post-combusted by O2/preheated air inside the smelter. Processes such as HIsmelt, DIOS, AISI-DOE, etc., belong to this group. Based on above objectives and concepts, development work was carried out for several processes. Fig 3 Concept of two stage SR process utilizing O2 and coalwithout and with post combustion. The concepts of single stage and two stage processes utilizing coal and electricity is shown in Fig 1. A further development of the concept has been in the direction of making the reduction stage in the upper part of the melting reactor rather than a separate process unit, giving a continuous counter current oxy/coal smelting reduction process. Many speculate that smelting originated from the ancient Middle East (5000 B.C.). It will take less then a minute, Technological and other processes/equipments associated with steel industry, Management in steel plant along with training and development, Raw materials and other materials used in steel plants, Marketing Concepts and Comparison with Selling Concepts, Bulk Material Storage and Storage Yard Machines, Role of Safety and its Importance in a Steel Organization, Role of Leadership in the Management of Organizations. The lower popularity of DR processes provided incentives towards development of SR ironmaking process route. The process gives improved energy economy by utilizing exhaust gases for electricity generation. It is possible to recycle of existing stock-piles, in-plant dusts, sludge and other reverts to the extent possible. Basic oxygen steelmaking (BOS) based process concepts – During the late 1970s and early 1980s there was considerable interest in methods of reducing the costs of BOS route of production by enhancement of the scrap melting capability of the process. The use of bulk O2, which has been widely available, offered a method of achieving high process temperatures without the necessity for hot blast stoves, and since O2 is normally available at high pressure there is no requirement for large air blowers. The chemical change is one in which the substance loses or gains an electron (oxidation or reduction). Romelt and Ausmelt processes are examples for this SR process. 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