The coalbased direct reduction characteristics of lowgrade iron ore during lignite pyrolysis were investigated. Especially, the coal used as reducing agent contains a high percentage of volatile matter and a low percentage of fixed carbon, which could produce a large amount of H 2 and CO during pyrolysis at high temperature and improve the speed of reduction reaction.
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The first process of the route is the production of hydrogen by water electrolysis using CO 2 lean electricity. The challenge is to achieve massive production of H 2 in acceptable economic conditions. The second process is the direct reduction of iron ore in a shaft furnace operated with hydrogen only.
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Direct reduced iron (DRI) is the product which is produced by the direct reduction of iron ore or other iron bearing materials in the solid state by using noncoking coal or natural gas. Processes which produce DRI by reduction of iron ore below the melting point of the iron are normally known as the direct reduction (DR) processes.
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Iron ore reduction is an important process in the iron/steelmaking industry, where iron ore is reduced to metallic iron, usually with coal, coke, natural gas, CO, or hydrogen as the reducing agents. ... direct reduction (DR)—electric arc furnace (EAF). Sponge iron instead of liquid hot metal is produced and then this direct reduced iron is ...
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Energyefficient Technologies in Direct Reduction of Iron Process 17 Waste Heat Recovery for Power Generation 18 Iron Ore Preheating Rotary Kiln Using Waste Heat Recovery System 20 Coal Gasification for Partial Substitution in Rotary Kiln 22 Waste Heat Recoverybased Absorption Chiller 23
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Recent Achievements in Conventional Coal Gasification Processes. Stroud(General Rapporteur), in Oils and Gases from Coal, 1980 Reducing Gases. There are three ways in which gases can be used in ironmaking. They can be injected into the tuyeres and boshes of blast furnaces to obviate the use of oil or natural gas or used for direct ore reduction.
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Context 1 ... Using solid reductant, that is, coalbased DR process 2. Using gaseous reductant, that is, gasbased DR process DR processes are summarized in Table 1. ... View in fulltext...
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The blast furnace and direct reduction processes have been the major iron production routes for various iron ores ( goethite, hematite, magnetite, maghemite, siderite, etc.) in the past few ...
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The reduction process takes place in the reduction tower. A tower is the heart of the plant. The direct reduction process is a complex process, which, explained in simple terms, consists of the following steps: Raw material iron ore pellets: Iron ore pellets the raw material are fed into the reactor; Natural gas is converted into ...
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The process principles are the basis for numerous rotary kiln plants and still represent the dominant technology for the direct reduction of lump ore or pellets using coal. Operates with the widest range of ironbearing materials, such as pellets, lump ore, beach sand, ilmenite and also iron ore fines with SL/RNXtra.
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The RHF process was originally developed as an alternative to gasbased direct reduction, making DRI from iron ore and coal. The process started from the patent of D. Beggs applied by MidlandRoss Corporation in 1965 [144]. This process was known as Heat Fast [145].
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Table 2: Specific hydrogen consumption and requirements for direct reduction Besides the hydrogen needed for the reduction of iron ore, energy is also required to heat the reducing gas. In the conventional direct reduction process this energy derives from a partial stream of the top gas of the Midrex shaft. Usage of
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Coalbased direct reduction of nickel slag and magnetic separation of iron are effective methods of secondary resource utilization. The growth characteristics of metallic iron particles in this process are of great significance for subsequent grinding and magnetic separation process. The nickel slag is mixed with coal powder and other additives in a certain proportion, and then subjected to a ...
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DRI production Direct reduction of iron is the removal of oxygen from iron ore or other iron bearing materials in the solid state, without melting, as in the blast furnace. The reducing agents are carbon monoxide and hydrogen, coming from reformed natural gas, syngas or coal. Iron ore is used mostly in pellet and/or lumpy form.
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The rotary kiln DRI process offers 11% and % lower GHG emissions on the lowest and highest end of the sensitivity band, when compared to the coal gasifier DRI process. However, if ore pelletization is uniformly considered for all DRI process, the emissions of the coal gasifier process could be up to % lower than the rotary kiln process ...
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Contact. Maximising coal recovery in challenging geologies represents a significant efficiency opportunity for most coal mining operations to increase the value of their resource. As the easy coal is mined out, mine operators need to become more skillful at mining thin, steep, deep and undulating seams productively and without sacing coal ...
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In this paper, we propose and assess a potential design for a fossilfree steelmaking process based on direct reduction of iron ore with hydrogen. We show that hydrogen direct reduction steelmaking needs MWh of electricity per tonne of liquid steel, mainly for the electrolyser hydrogen production. ... but instead of coal and coke the ...
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The aim is to produce steel by the direct reduction of iron ore with hydrogen, which would completely replace coke as a reducing agent. ... The direct reduction demonstration plant enables us to optimize the reduction process and how it interacts with the other process steps. ... Coal (166) CoaltoLiquids (CTL) (184) Compressed Air Engines (16)
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Methods of producing low carbon wrought iron directly from the ore are known as direct reduction process. After the development of the blast furnace, the DR processes ... Codir stands for coal, ore direct reduction. It is very similar to KruppRenn process but operates comparatively at a much lower temperature. Here limestone or dolomites are
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DRI production requires lower temperatures for its direct reduction reaction and is a solidstate process at temperatures below the melting point of iron (1200 °C). Reduction gas (commonly a mixture of H2 and CO syngas) is typically made from either natural gas or coal.
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In a typical direct reduction process, coal and natural gas are used as alternative fuels to replace metallurgical coke. However, there is no fundamental improvement in the environmental pollution control for the direct reduction technology, especially concerning the carbon emissions, compared to the traditional ironmaking technology [1], [2], [3].
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The gasbased direct reduction of iron ore pellets was carried out by simulating the typical gas composition in coal gasification process, Midrex and HylIII processes. The influences of gas composition and temperature on reduction were studied. Results show that the increasing of H2 proportion is helpful to improve the reduction rate. However, when φ(H2):φ(CO)>:1, changes of H2 content ...
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An innovative coalbased direct reduction process of lowgrade iron ore coal composite minipellets in lowtemperature rotary kiln has been developed by Central South University. In this approach, 38 mm pellets were made of mixture of sodium additives, iron ore and coal.
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Coal exporters could also lose income, as we're the largest exporter of the coking coal burnt in furnaces using current technology. ... But in the direct reduction process, the iron ore doesn ...
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Noncoking coal resources are very rich in China; research and development of coalbased direct reduction process (such as FASTMET and ITMK3 process) has important practical significance, and it can strengthen the comprehensive utilization on lowgrade iron ore, associated mineral resources, and iron and steel plant dust and sludge.
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Kobe Steel has developed coalbased direct reduction (DR) technologies, the FASTMET, FASTMELT and ITmk3 processes, which reduce carbon composite agglomerates (pellets or briquettes) on the hearth of a rotary hearth furnace (RHF). This paper outlines the features of each process, status of technical development and commercialization.
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DR processes reduce iron ore in its solid state by the use of either natural gas or coal as reducing agents, and they have a comparative advantage of low capital costs, low emissions and...
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The Fe3O4 and Fe2SiO4 in copper slag were successfully reduced to metallic iron by coalbased direct reduction. Under the best reduction conditions of 1300 °C reduction temperature, 30 min reduction time, 35 wt.% coal dosage, and 20 wt.% CaO dosage ( binary basicity), the Fe grade of obtained iron concentration achieved %, and the Fe recovery was %. The kinetic studies on ...
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agglomerate fine iron ore dust in conjunction with other material (typically limestone) to form a product that can be added to the blast furnace. Another alternative to hot molten iron making is the direct reduction method. In this method, iron is reduced in its solid state using either coal or natural gas as a fuel.
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Direct reduced iron ( DRI ), also called sponge iron, [1] is produced from the direct reduction of iron ore (in the form of lumps, pellets, or fines) into iron by a reducing gas or elemental carbon produced from natural gas or coal. Many ores are suitable for direct reduction.
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One of the advantages of char over raw coal is less complicated reduction process due to removal of volatiles during pyrolysis and lack of pollutionforming materials. ... McElwain DLS, Wibberley LJ. Experimental study of coal based direct reduction in iron ore/coal composite pellets in a one layer bed under nonisothermal, asymmetric heating ...
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Iron making. The primary objective of iron making is to release iron from chemical combination with oxygen, and, since the blast furnace is much the most efficient process, it receives the most attention here. Alternative methods known as direct reduction are used in over a score of countries, but less than 5 percent of iron is made this way. A third group of ironmaking techniques classed as ...
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Background In a DR process, iron ore pellets and/or lump iron ores are reduced by a reducing gas to produce DRI or hot briquetted iron (HBI). Depending on the generation of the reducing gas, two different DR processes are commercially available: gasbased and coal/oilbased.
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KruppCodir Process: Codir stands for coal, ore direct reduction. It is very similar to KruppRenn process but operates comparatively at a much lower temperature. Here limestone or dolomites are charged into the kiln. The first Codir plant started its operation in 1973 in South Africa.
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