Modelling the Reduction of an Iron Ore-Coal Composite …
Shi et al. later developed a non-isothermal model for the direct reduction of iron-ore coal composite pellet and reported that the effect of heat convection in the pellet on the overall degree of ...
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Direct Reduction Ironmaking | SpringerLink
Coal-Based Direct Reduction Ironmaking. Non-coking coal or carbon-bearing material is used as reductant and heating source, and the iron ore in solid phase is reduced into iron metal in various reactors. The industrialized process is rotary kiln process. There are also fixed bed process, shaft furnace process, and rotary hearth furnace …
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Solid-State Metalized Reduction of Magnesium-Rich Low
Ma et al [10] also studied the solid-state metalized reduction of garnierite for recovering iron and nickel at 1200-250°C with 8 wt% coal and 7 wt% CaF 2 for 20-40 min, and the recovery rates ...
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Solid State Reduction of Preoxidized Chromite-iron Ore …
The reduction of both chromite and iron ore is heavily dependent on the carbon monoxide partial pressure in the reactor. More coal addition means stronger reducing atmo- sphere (higher carbon partial pressure) and longer mainte- nance time, in other words, the prereduced pellets are less likely to be re-oxidized.
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Reduction of iron ore pellets with domestic lignite coal in …
Temperature Reduction of iron ore pellets with lignite coal was investigated at the temperatures of 910, 950, 1000 and 1050°C with different coal consumption ratios. There is a marked effect of temperature on the metallization degree which is shown in Figs. 4 and 5 for coal consumption ratios of 0.40 and 0.48, respectively.
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An experimental study of direct reduction of hematite by …
The reduction of iron oxide by coal takes place essentially in three subprocesses : (a) ... Chowdhury GM, Roy GG. Application of genetic algorithm (ga) to estimate the rate parameters for solid state reduction of iron ore in presence of graphite. Comp Mater Sci. 2009;45:176–80. Article CAS Google Scholar ...
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Review Low-carbon production of iron and steel: Technology options
DRI production requires lower temperatures for its direct reduction reaction and is a solid-state process at temperatures below the melting point of iron (1,200°C). Reduction gas (commonly a mixture of H 2 and carbon monoxide [CO] syngas) is typically made from either natural gas or coal. Two of the main reduction reactions in the kiln: …
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Review on Reduction Kinetics of Iron Ore–Coal Composite
Abstract The use of iron ore–coal composite pellet as a raw material for iron making is an ongoing area of research. Investigations on composite pellet reduction have reported some interesting phenomena, and experimental and modeling results, in which consistent and inconsistent conclusions have been presented in the literature. The aim …
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Carbothermic Reduction of Nickeliferous Laterite Ores for …
Both the consumption and production of crude stainless steel in China rank first in the world. In 2011, the nickel production in China amounted to 446 kilotons, with the proportion of electrolytic nickel and nickel pig iron (NPI) registering 41.5% and 56.5%, respectively. NPI is a low-cost feedstock for stainless steel production when used as a …
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Solid-state reduction kinetics and mechanism of pre …
purpose of this work is to investigate the solid-state kinetics of pre-oxidized vanadium−titanium magnetite concentrate reduction with coal. The phase and the microstructure of the reduction product were characterized by XRD, SEM and EDS, based on which the mechanism of the solid-state reduction was studied. 2 Experimental 2.1 …
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Investigate the reduction of mill scale with low grade coal …
Direct reduction is a reduction process comprising of oxygen removal from the iron ore in its solid state. ... Influence of temperature and time on reduction behavior in iron ore–coal composite pellets. Powder Technol., 256 (2014), pp. 361-366, 10.1016/j.powtec.2014.02.039.
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The direct solid-solid reaction between coal char and iron …
Coal char prepared from PRB coal (Power River Basin coal, USA) was used as solid fuel in order to mitigate the complexity of coal volatility and moisture in the initial reaction. In coal char preparation, the raw coal with a particle size of 90–500 μm was heated to 800 °C in a fixed bed reactor at a rate of 20 °C/min and then held at 800 ...
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Direct Reduced Iron (DRI) | International Iron Metallics …
Direct Reduced Iron (DRI) is the product of the direct reduction of iron ore in the solid state by carbon monoxide and hydrogen derived from natural gas or coal. See more information about the production of DRI . Most gas-based direct reduction plants are part of integrated steel mini-mills, located adjacent to the electric arc furnace (EAF ...
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Direct Reduction Iron | SpringerLink
The chemical composition of direct reduction iron requires that the metallization ratio be 92–96%, FeO content 3–15%, gangue content 1–4%, phosphorus content less than 0.06%, sulfur content less than 0.03%, and content of each of the nonferrous metal impurities Cr, Ni, Cu, and Pb less than 0.01%. Other indicators, …
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Solid-state reduction of an Indonesian iron sand …
ABSTRACT The reduction of an Indonesian iron sand concentrate was studied using TG/DTA and XRD analyses. The iron sand concentrate was mixed with coal and formed into a cylindrical pellet. The experimental results show that magnetite was reduced into wustite at 700–800°C and into metallic iron at temperature above 800°C. …
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The Direct Reduction of Iron
In reduction using RKs, lump coal and iron oxide pellets are added separately and the amount of coal can be easily varied. Also the char formed during the process is recycled and used as feed as well. ... Because the direct reduction of iron is a solid-state process, the product DRI has roughly the same size and shape as the …
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Reduction of Iron Ore Fines using "SYNGAS" from …
has been designed with an in-situ coal-pyrolysis mechanism for the solid-state reduction of the briquetted fines. In this way, devolatilization and reduction have been achieved inside a single ...
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(PDF) i) Direct Reduced Iron: Production
Processes that produce iron by reduction of iron ore (in solid state) below the melting point are generally classified as DR processes. Based on the types of reductant used, DR processes can be ...
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Reduction of Iron Ore Fines using "SYNGAS" from Lean- Grade Coal
An energy-efficient laboratory furnace has been designed with an in-situ coal-pyrolysis mechanism for the solid-state reduction of the briquetted fines. In this way, devolatilization and reduction ...
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Solid State Reduction of Iron, Manganese and Chromium Oxide …
Iron ore containing titanium and vanadium could be reduced significantly in the solid state with methane-hydrogen mixture up to 400 °C lower than is needed in ordinary solid state carbothermic process. The reduction of chromite and manganese ores were possible similarly at lower temperatures with potential energy savings lower carbon …
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Low-Carbon Production of Iron & Steel: Technology Options …
DRI production requires lower temperatures for its direct reduction reaction and is a solid-state process at temperatures below the melting point of iron (1200 °C). ... It can allow non-coking coal and low-cost iron ores (outside BF quality range) to produce iron with 20% less carbon footprint [(Quader et al., 2016)]. Commercial level ...
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Sponge Iron | SpringerLink
Sponge iron means porous iron produced by direct reduction process.Direct reduction (DR) process is a solid-state reaction process (i.e. solid–solid or solid–gas reaction) by which removable oxygen is removed from the iron ore, using coal or reformed natural gas as reductants, below the melting and fusion point of the lump ore or …
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(PDF) DIRECT REDUCED IRON ORE: Production
This product is known as Direct Reduced Iron (DRI) or Sponge Iron. Processes that produce iron by reduction of iron ore (in solid state) below the melting point are generally classified as DR ...
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Solid-State Reduction Studies for Recovery of Iron from …
The first step is related to the recovery of iron and pyrometallurgical methods (solid-state reduction and smelting) are currently being performed. Nonferrous metals will then be selectively leached in the second step. In TMS 2019, the authors outlined the literature related to the smelting studies for iron recovery from bauxite …
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Solid State Reduction of Preoxidized Chromite-iron Ore …
A comparative study on coal-based solid state reduction of preoxidized chromite pellets and chromite-iron ore pellets was conducted to investigate the reduction behavior of these two types of pellets. And the enhancement mechanism of chromite reduction reactions due to the pre-oxidation process of chro-mite with magnetite was revealed by means ...
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Reduction Enhancement Mechanisms of a Low-Grade Iron Ore–Coal Composite
The reduction behavior of a low iron grade with high SiO2 content ore–coal composite was investigated in the temperature range of 1143 K to 1263 K (870 °C to 990 °C). Sodium chloride was chosen as an additive to promote this reduction process. The effect of the sodium chloride addition and its mechanism was also investigated. Results …
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Improvement in Sinter Properties with Reduction in …
In the sintering of iron ores, the partial substitution of anthracite coal for coke breeze has been considered to be an effective way of reducing emissions and improvement in sintering properties. In the present study, the combustion characteristics of the anthracite coal and coke breeze were investigated and its influence on product sinter quality and …
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Hydrogen-based pre-reduction of chromite: Reduction and …
However, in the later stages, a combination of solid-state diffusion and inter-facial chemical reactions was identified as the rate-controlling step. Furthermore, Daniel [31] concluded that in the reduction of chromite with hydrogen, the phase-boundary reaction and nucleation play a significant role in controlling the process.
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Recent Trends in the Technologies of the Direct Reduction …
In a typical reduction-smelting process, the iron ore will first undergo a solid-state reduction in the pre-reduction unit. The resulting product is then smelted and further reduced in the smelting-reduction vessel where the coal gasification occurs, thus delivering heat and carbon-monoxide-rich hot gas.
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Production of Pig Iron from Magnetite Ore–Coal Composite …
Magnetite ore–coal composite pellets with about 10, 15 and 20 mm diameter were rapidly smelted to produce pig iron by microwave heating in N2 gas. A microwave generator with 5 kW maximum power at 2.45 GHz was employed. Carbon content in pig iron was about 2 mass% near the liquidus line in the Fe–C system. Slag was easily …
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