A mathematical model has been developed to predict the operating behavior of an SL/RN direct reduction kiln from a knowledge of the main process variables. The model is based on steady state principles and is capable of quantitatively describing the different chemical reactions in the kiln such as reduction, Boudouard reaction, coal devolatilization, …
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The SL/RN process is a proven coal-based direct reduction technology, its versatility being characterised by flexibility in the use of raw materials (lump ores, pellets, iron …
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The SL/RN Process For Production of Metallized Burden by Kurt Meyer, Gunter Heitmann, and Wolfgang Janke ... Fig. l-Flowsheet of a SL/RN direct reduction plant with anthracite or coke as reducing agent, 140 0 -,----120 0 100 0 80 0 W~ STE G~ S 0 V ~ 60 40 v-20 0 o FEED EN:), f---r-
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In the direct reduction of iron ore Outotec has been involved since this technology was first introduced, as one of the inventors of the SL/RN-process based on the rotary …
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Our direct reduction offering covers: • Design, engineering, delivery, and services for traditional SL/RN direct reduction plants based on a rotary kiln, with non-coking coal as …
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In the steel plant considered here, direct reduced iron (DRI), produced by the coal-based SL/RN process, makes up 50% or more of the total iron charge. SL/RN DRI samples from a kiln cooler had high nitrogen contents (50-250ppm, depending on particle size), contributing to elevated nitrogen levels in liquid steel produced in the EAFs.
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SL/RN. The SL/RN process has a long development history, as summarized elsewhere [[50], [51], [52]]. There are currently 10 facilities listed in the Midrex database with capacities greater than 50,000 tpy [60]. Nearly half of this volume is at one location in South Africa. The remainder is in India, with individual (idled) units in Brazil and Peru.
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Unlike blast furnaces, direct reduction ironmaking plants using natural gas (e.g., the MIDREX process and HYL process) have the characteristics of requiring a smaller capital expenditure and no coking coal. Many direct reduction plants have been built in developing contries, particularly those that produce natural gas.
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In this report coal-based direct reduction processes that are currently in commercial operation or under development are discussed and compared. The coal-based processes can be grouped into four categories according to their reduction reactors. The rotary kiln processes include ACCAR/OSIL, DRC, Krupp-CODIR and SL/RN processes.
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Direct reduction processes are those where the iron ore is reduced to metallic iron at temperatures below the melting point of iron. From: ... (for example, SL/RN and iron …
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In the direct reduction of iron ore Outotec has been involved since this technology was first introduced, as one of the inventors of the SL/RN-process based on the rotary kiln and as a successful licensee of the Midrex shaft furnace process (the Lurgi legacy of the company).
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Download scientific diagram | Schematic arrangement of SL/RN direct reduction kiln. [2] from publication: COMPARISON OF DIFFERENT COAL BASED DIRECT REDUCTION PROCESSES | In this report coal-based ...
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Sponge Iron or Direct Reduction Iron (DRI) refers to a porous metallic substance that is produced by the direct reduction of iron ore, where oxygen is removed from the iron oxide using coal or ...
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A one-dimensional steady-state mathematical model is proposed for direct reduction process in rotary kilns akin to the SL/RN process. The model takes into account pneumatic coal char injection from the discharge end of the kiln to supplement the heat availability. The model is based on material and energy conservation principles, and the empirical …
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Direct reduction (DR) processes like SL/RN (1970), ACCAR (1973), Krupp (1973), CODIR, TDR (1975), etc., using rotary kiln as a reactor and coal as a reductant, have been developed worldwide. India, due to its large reserve of non-coking coal, has shown keen interest in pursuing these technologies using such coal as a cheap energy …
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Midrex and HYL processes are generally used for gas based reduction and SL/RN ... Direct reduction is defined as a process in which metallic iron is produced by reducing
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The process of direct reduction . The process of direct reduction is carried out in a rotary kiln where the operating temperatures are maintained in a range from 1,000 deg C to 1,100 deg C. The product of the kiln (DRI …
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HyL/Energiron, Finmet, Circored, SL/RN, ITmk3; worldwide production of DRI/HBI; briquetting of DRI Introduction The name "direct reduction" is misleading because these reduction processes are not a "more direct" route to steel than the blast furnace. Nor does the term have anything to do with direct reduction in the blast furnace.
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Direct Reduction Processes Direct reduction is defined as a process of producing solid iron product out of small-grain ore, lump ore or pallets, applying natural gas or coal-based reducing agents at relatively low temperatures i.e. at around 1000OC. ... ROMELT, AISI, CCF - Direct reduced iron (DRI) – "sponge": MIDREX, HYLSA, SL/RN ...
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since this technology was first introduced as one of the inventors of the SL/RN-process based on the rotary kiln and as a successful licensee of the Midrex shaft furnace process. ... For the direct reduction of fine iron ore, Circored applies a two-stage reactor configuration with a CFB followed by a bubbling fluidized bed (FB) downstream.
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A mathematical model has been developed to predict the operating behaviour of an SL/RN direct reduction kiln from a knowledge of the main process variables. The model is based on steady state principles and is capable of quantita• tively describing the complex chemical reactions in the kiln such as reduction, Boudouard reaction, coal ...
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Nitrogen in SL/RN direct reduced iron: origin and effect on nitrogen control in EAF steelmaking. ... The SL/RN DRI samples from a kiln cooler had high nitrogen contents (50–250 ppm, depending on particle size), contributing to elevated nitrogen levels in liquid steel produced in the electric arc furnaces. The proposed …
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In book: Encyclopedia of Iron, Steel, and Their Alloys (pp.pp 1082-1108) Chapter: i) Direct Reduced Iron: Production; Publisher: CRC Press, Taylor and Francis Group, New York.
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B) Direct Reduction Process, where reduction gas is generated from hydrocarbons in the reduction Process – Coal Based Process - Rotary Kiln Process (ACCAR / SL – RN / Krupp CODIR)
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The SL/RN DRI samples from a kiln cooler had high nitrogen contents (50–250 ppm, depending on particle size), contributing to elevated nitrogen levels in liquid steel produced in the electric arc furnaces. The proposed mechanism of nitriding of SL/RN DRI involves gaseous nitrogen (present within the rotary cooler… Expand
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At present, the mainstream process of coal-based direct reduction in the world is mainly the rotary kiln method, and its process flowchart is shown in Fig. 1.The existing rotary kiln processes in the world mainly include the German Ruch process (SL/RN), German Krupp Codir process, British AccAR process, Indian TDR process, …
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The SL//RN process is one of thedirectreduction processes operated on a commercialbasis.7-1° It is distinguished from the other direct reduction pro-cessesby its use of solid coal as the reducing agent ratherthan a gaseous reductant, and by its use of a rotary kiln as thereactorratherthan a vertical shaft. The importance of this process ...
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Production of direct reduced iron from indigenous raw materials is an attractive alternative to the use of scrap for electric steelmaking or for a DR-based integrated steel plant. The SL/RN process is a proven coal-based direct reduction technology, its versatility being characterised by flexibility in the use of raw materials (lump ores, pellets, iron-bearing …
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Typical gas-based direct reduction processes are Midrex and HYL processes, both of which are shaft furnace processes that use natural gas (CH 4) or coal gas as reductant. Coal-based direct reduction processes include rotary kiln process (e.g., SL/RN process and DRC process), rotary hearth furnace process, and multilayer rotary …
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The initial trials with CO + H 2 mixed gas started with processes such as MIDREX, HYL, and SL/RN, among others. By the 1980s, technological routes utilizing coal as a reducing agent had entered the industrial production phase, such as FINMET, ... Fluidized bed direct reduction of iron, (a) production process (Schenk, 2011), (b) ...
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