Effect of flux addition and reductant type in smelting process of Indonesian limonite ore in electric arc furnace

Iron sand as the largest form of iron ore reserves in Indonesia has not been optimized properly for domestic iron-steel production. In the production chain of pig iron from iron sand, there is a problem that in sponge iron (result of direct reduction) contains many impurities, especially titanium. This research is conducted to determine the effect of additive variation to the Fe content and Fe recovery during sponge iron smelting process into pig iron using electric arc furnace (EAF). Types of additives variation that used in this research are CaCl2 and CaC2, as well as smelting without additive as comparison. Briquettes made from sponge iron, coal, flux (SiO2), and variations of additive are melted in crucible using EAF (16.2 Volt; 180 Ampere) for 6 minutes. Based on EDX and XRD results of pig iron and slag, the optimum process of sponge iron smelting is use the CaCl2 as additive. It’s shown by the result that the pig iron containing the highest %wt Fe by 90.97% and the highest Fe recovery by 80.41%. The product that used CaC2 as additive has Fe content of 89.31 %wt and Fe recovery during process of 72.36%. Meanwhile, the results obtained from the smelting without additives only shows that the Fe content in pig iron amounted to 88.90 %wt and 68.76% values for Fe Recovery.

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Numerical Simulation of Bottom-Blowing Stirring in Different Smelting Stages of Electric Arc Furnace Steelmaking

Metals ◽

10.3390/met11050799 ◽

2021 ◽

Vol 11 (5) ◽

pp. 799

Author(s):

Hang Hu ◽

Lingzhi Yang ◽

Yufeng Guo ◽

Feng Chen ◽

Shuai Wang ◽

...

Keyword(s):

Numerical Simulation ◽

Molten Steel ◽

Steel Slag ◽

Electric Arc Furnace ◽

Electric Arc ◽

Simulation Software ◽

Model Verification ◽

Smelting Process ◽

Arc Furnace ◽

Bottom Blowing

Electric arc furnace (EAF) steel bottom-blowing can effectively improve the temperature and composition uniformity of the molten pool during smelting process. To explore the effect of molten-steel characteristics on bottom-blowing at various stages of smelting, we divided the smelting process of the EAF into four stages: the melting stage, the early decarburization stage, the intermediate smelting stage, and the ending smelting stage. The numerical simulation software ANSYS Fluent 18.2 was used to simulate the velocity field of molten steel under the condition of bottom-blowing stirring in different stages in EAF steelmaking process. The properties of bottom-blowing and the kinetic conditions of the steel-slag at this interface were investigated. Our results showed that at a bottom-blowing gas flow rate of 100 L/min, the average flow rates of the four stages were v1 = 0.0081 m/s, v2 = 0.0069 m/s, v3 = 0.0063 m/s, and v4 = 0.0053 m/s. The physical model verification confirmed the results, that is, the viscosity of molten steel decreased as the smelting progressed, and the flow velocity of the molten steel caused by the agitation of bottom-blowing also decreased, the effect of bottom-blowing decreased. Based on these results, a theoretical basis was provided for the development of the bottom-blowing process.

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Analytical Electron Microscopy Characterization of Electric Arc Furnace Dust

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100097326 ◽

1981 ◽

Vol 39 ◽

pp. 134-135

Author(s):

J. R. Porter ◽

J. I. Goldstein ◽

D. B. Williams

Keyword(s):

Electron Microscopy ◽

Analytical Electron Microscopy ◽

Electric Arc Furnace ◽

Electric Arc ◽

Dust Particles ◽

Particle Analysis ◽

Arc Furnace ◽

Analytical Electron ◽

Residual Elements ◽

Industry Practice

Alloy scrap metal is increasingly being used in electric arc furnace (EAF) steelmaking and the alloying elements are also found in the resulting dust. A comprehensive characterization program of EAF dust has been undertaken in collaboration with the steel industry and AISI. Samples have been collected from the furnaces of 28 steel companies representing the broad spectrum of industry practice. The program aims to develop an understanding of the mechanisms of formation so that procedures to recover residual elements or recycle the dust can be established. The multi-phase, multi-component dust particles are amenable to individual particle analysis using modern analytical electron microscopy (AEM) methods.Particles are ultrasonically dispersed and subsequently supported on carbon coated formvar films on berylium grids for microscopy. The specimens require careful treatment to prevent agglomeration during preparation which occurs as a result of the combined effects of the fine particle size and particle magnetism. A number of approaches to inhibit agglomeration are currently being evaluated including dispersal in easily sublimable organic solids and size fractioning by centrifugation.

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