Confocal Microscopic Studies on Evolution of Crystals During Oxidation of the FeO-CaO-SiO2-MnO Slags

Semykina, Anna; Nakano, Jinichiro; Sridhar, Seetharaman; Shatokha, Volodymyr; Seetharaman, Seshadri

doi:10.1007/s11663-010-9392-2

Cited by 39 publications

(27 citation statements)

References 5 publications

(3 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The sample (actual) temperature showed a negative deviation compared with the holder temperature. [8] III. RESULTS…”

Section: Confocal Scanning Laser Microscopementioning

confidence: 99%

“…The details of the synthesis were described in the previous work. [8] Platinum crucibles for holding the slags were 99.99 pct in purity and had dimensions of 5 mm in diameter 9 5 mm in height 9 0.4 mm in thickness. Argon National Gas (Pittsburgh, PA).…”

Section: A Materials and Sample Preparationmentioning

confidence: 99%

“…The experimental assembly has been described in detail in the previous publication. [8] It should be noted that at the beginning of the oxide formation, the gas oxygen potential had likely not reached its desired value and the slag would not be equilibrated with the atmosphere. The experiments were performed above the liquidus temperature of the slag.…”

Section: Confocal Scanning Laser Microscopementioning

confidence: 99%

See 2 more Smart Citations

Confocal Scanning Laser Microscopy Studies of Crystal Growth During Oxidation of a Liquid FeO-CaO-SiO2 Slag

Semykina

Nakano

Sridhar

et al. 2011

Metall Mater Trans B

Self Cite

View full text Add to dashboard Cite

The oxidation of FeO in 30 wt pct FeO-35 wt pct CaO-35 wt pct SiO 2 slag was investigated as part of a wider study on the recovery of Fe units through magnetic separation. A confocal scanning laser microscopy (CSLM) technique was used to visualize the oxidation of FeO in the liquid slag. The formation event was observed in situ under the CSLM and the onset of precipitation on a surface of the slag liquid was recorded at various temperatures in an oxidizing atmosphere. A Time-Temperature-Transformation (TTT) diagram was constructed based on the CSLM results. Samples obtained from the CSLM heating chamber were analyzed by a scanning electron microscope (SEM) equipped with an energy-dispersive spectrometer (EDS).

show abstract

“…The sample (actual) temperature showed a negative deviation compared with the holder temperature. [8] III. RESULTS…”

Section: Confocal Scanning Laser Microscopementioning

confidence: 99%

Section: A Materials and Sample Preparationmentioning

confidence: 99%

Section: Confocal Scanning Laser Microscopementioning

confidence: 99%

See 1 more Smart Citation

Confocal Scanning Laser Microscopy Studies of Crystal Growth During Oxidation of a Liquid FeO-CaO-SiO2 Slag

Semykina

Nakano

Sridhar

et al. 2011

Metall Mater Trans B

Self Cite

View full text Add to dashboard Cite

show abstract

“…The steel industry produces large volumes of waste slag with huge sensible heat (at extremely high temperature >1500°C) and considerable amount of metals (Fe, Mn, V, Cr, Semykina et al (2010aSemykina et al ( , 2010bSemykina et al ( , 2011b. This promising method may enable efficient selective recovery of transitional metal oxide from steelmaking slags, especially for the CaO-SiO2-FeO(-MnO-V2O3) bearing steelmaking slag.…”

Section: Introductionmentioning

confidence: 99%

Development of a novel process for energy and materials recovery in steelmaking slags

Bhattacharjee

et al. 2017

Mineral Processing and Extractive Metallurgy

Self Cite

View full text Add to dashboard Cite

. (2017) Development of a novel process for energy and materials recovery in steelmaking slags. Mineral Processing and Extractive Metallurgy , 126 (1-2). pp. 94-105. Permanent WRAP URL:http://wrap.warwick.ac.uk/83697 Copyright and reuse: The Warwick Research Archive Portal (WRAP) makes this work by researchers of the University of Warwick available open access under the following conditions. Copyright © and all moral rights to the version of the paper presented here belong to the individual author(s) and/or other copyright owners. To the extent reasonable and practicable the material made available in WRAP has been checked for eligibility before being made available.Copies of full items can be used for personal research or study, educational, or not-for profit purposes without prior permission or charge. Provided that the authors, title and full bibliographic details are credited, a hyperlink and/or URL is given for the original metadata page and the content is not changed in any way. A note on versions:The version presented here may differ from the published version or, version of record, if you wish to cite this item you are advised to consult the publisher's version. Please see the 'permanent WRAP URL' above for details on accessing the published version and note that access may require a subscription. Development of a novel process for energy and materials recovery in steelmaking slagsThis work aims at gathering fundamental knowledge for the development of a novel process for energy (H2 gas) and materials (magnetite Fe3O4) recovery in hotsteelmaking slags by reacting molten steelmaking slag with steam.Thermodynamic simulation was carried out to calculate the accumulated amount of produced H2 gas as a function of the volume of H2O-Ar gas introduced and the precipitated phases of the molten slags during controlled cooling. Laboratory experiments of crystallisation behaviours of molten slags during cooling were visualized in situ through a confocal laser scanning microscope (CSLM), and the cooled slags obtained were characterised by using SEM-EDS and XRD. CCT diagrams for different slags were created showing the slag crystallisation/phase transformation at different cooling rates. The recovery ratio of H2 gas and the maximum potential recovery ratio of iron oxide in the oxidised slags were calculated, which concludes that with increasing the slag basicity from 1.0 to 1.5 and 2.0, the recovery ratio of H2 was found to increase from 12.6% to 23.7% and 22.6%, and the maximum potential recovery ratio of iron oxide was found to increase from 18.3% to 34.4% and 32.8% under the investigated conditions.Keywords: steelmaking slag; H2 gas; spinel; CCT diagram; recovery IntroductionThe steel industry produces large volumes of waste slag with huge sensible heat (at extremely high temperature >1500°C) and considerable amount of metals (Fe, Mn, V, Cr, Semykina et al. (2010aSemykina et al. ( , 2010bSemykina et al. ( , 2011b. This promising method may enable efficient selective recovery of transitional metal oxide from steel...

show abstract

“…[10,11] The crystal precipitation during synthetic slag oxidation was observed using confocal scanning laser microscopy. [12] Precipitated phases were magnetite and manganese ferrite in the spinel form. From the technological point of view, the slag can be subjected to oxidation or cooling.…”

mentioning

confidence: 99%

Recovery of Manganese Ferrite in Nanoform from the Metallurgical Slags

Semykina

Seetharaman

2010

Metall Mater Trans B

Self Cite

View full text Add to dashboard Cite

The present work investigates the formation of manganese ferrite of nanosize by oxidation of MnO-and FeO-containing slag. A horizontal resistance furnace was used as an experimental setup. The experiment was conducted in the temperature range of 1573 K to 1673 K (1300°C to 1400°C) in an oxidizing atmosphere. The samples were quenched to the cold end of the furnace and were analyzed by X-ray diffraction (XRD). The XRD patterns of the products showed the presence of two phases-manganese ferrite and calcium silicate. The particle size of the manganese ferrite was estimated by the Scherrer formula to be in the range of nanometers.The spinel-type, transition-metal ferrites have obtained increasing interest because of their wide area of technological applications in magnetic recording, [1] energy conversion and storage, [2] gas sensing, [3] and biotechnology. [4][5][6] To produce the ferrite nanoparticles, different methods have been used (e.g., thermal decomposition of organometallic precursors or reduction of metal salts, [7] coprecipitation method, and the sol-gel route [8] ). All these methods require pure reagents and energy consumption. The present work, however, shows the feasibility of the nanomanganese ferrite precipitation from the metallurgical wastes (metallurgical slags).Metallurgical plants produce millions of tons of slags every year. The main constituents of the slags are CaO, SiO 2 , Al 2 O 3 , MnO, FeO, and MgO. In Swedish and Ukrainian steelmaking practice, FeO content in the slag may reach up to 30 pct in some cases. These slags are only partially used in civil engineering, and the rest remains in dumps, increasing environmental burdens.The current authors proposed a way to recover iron from the liquid slags in the form of magnetite. [9] The concept was based on transformation of nonmagnetic wu¨stite (FeO) to magnetic magnetite (Fe 3 O 4 ) using an oxidizing atmosphere. Experiments on the ternary CaOFeO-SiO 2 and quaternary CaO-FeO-SiO 2 -MnO systems, followed by thermodynamic and kinetic modeling, were performed. [10,11] The crystal precipitation during synthetic slag oxidation was observed using confocal scanning laser microscopy. [12] Precipitated phases were magnetite and manganese ferrite in the spinel form. From the technological point of view, the slag can be subjected to oxidation or cooling. The solid slag may be crushed and the magnetic part, consisting of magnetite/ manganese ferrite, can be separated by the magnetic method and can be used again. The rest of the slag (nonmagnetic) effectively will be used in the production of a cement binder or in other applications. Alternatively, magnetite/manganese ferrite can be extracted from molten slags using crossed electric and magnetic fields. The cold model simulation of the particle movement in a conducting liquid under electromagnetic buoyancy force was investigated by the present authors earlier. [13] Theoretical application of the obtained data on the real magnetite particle-liquid slag system showed that magnetite will move with an approxi...

show abstract

Confocal Microscopic Studies on Evolution of Crystals During Oxidation of the FeO-CaO-SiO2-MnO Slags

Cited by 39 publications

References 5 publications

Confocal Scanning Laser Microscopy Studies of Crystal Growth During Oxidation of a Liquid FeO-CaO-SiO2 Slag

Confocal Scanning Laser Microscopy Studies of Crystal Growth During Oxidation of a Liquid FeO-CaO-SiO2 Slag

Development of a novel process for energy and materials recovery in steelmaking slags

Recovery of Manganese Ferrite in Nanoform from the Metallurgical Slags

Contact Info

Product

Resources

About