Ändra sökning
Avgränsa sökresultatet
1 - 8 av 8
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Träffar per sida
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
  • Disputationsdatum (tidigaste först)
  • Disputationsdatum (senaste först)
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
  • Disputationsdatum (tidigaste först)
  • Disputationsdatum (senaste först)
Markera
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 1.
    Berg, Martin
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    The effect of Al2O3, CaO and SiO2 on the phase relations in vanadium containing slags2015Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Today, the main raw material for vanadium production is vanadium containing steelmaking slags. The yield of the vanadium extraction process is affected by the composition of the slag, which in turn determines the phases present, the fractions of the phases and the distribution of the elements between the phases. The aim of this thesis was to experimentally investigate the effect of Al2O3, CaO and SiO2 on the phase relations in vanadium containing slags at 1673 K.

    Synthetic slags, in which the contents of Al2O3, CaO and SiO2 were varied individually, were equilibrated at 1673 K in a vertical resistance furnace. Closed molybdenum crucibles were used to set the oxygen potential of the individual samples.  The phases present, the phase compositions and the phase fractions of the samples were studied using SEM-EDS and LOM combined with an image analysis software.

    The results indicate that the samples consisted of a mixture of a vanadium and iron rich spinel phase and an iron and silicon rich liquid phase at 1673 K. Practically all the vanadium was concentrated into the spinel phase while no free silica or solid phases into which both calcium and vanadium concentrate to a significant extent were observed. The effect of Al2O3 on the phase compositions and the phase fractions was seen to be limited in the range studied. CaO primarily affected the composition of the liquid phases, while the effect on the phase fractions was small. SiO2 affected both the composition and fraction of the phases. The main effect was a decreased fraction of spinel phase, with an increasing vanadium content in the spinel phase as consequence.

    Ladda ner fulltext (pdf)
    fulltext
  • 2.
    Berg, Martin
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Lee, Jaewoo
    Hyundai Steel, 1480 Bukbusaneop Ro, Dangjin Si 31719, Chungnam, South Korea..
    Sichen, Du
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Partitioning of Calcium Between Liquid Silver and Liquid Iron2018Ingår i: Metallurgical and materials transactions. B, process metallurgy and materials processing science, ISSN 1073-5615, E-ISSN 1543-1916, Vol. 49, nr 3, s. 949-952Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The partitioning of calcium between liquid silver and liquid iron at 1823 K and 1873 K (1550 degrees C and 1600 degrees C) was studied experimentally using a closed molybdenum container. The calcium potential in the container was controlled by the composition of the alloys in equilibrium. The results agreed well with previous experimental measurements and indicated that the effect of temperature was not very pronounced in the temperature range studied.

  • 3.
    Berg, Martin
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Lee, Jaewoo
    Sichen, Du
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Mikro-modellering. KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Tillämpad processmetallurgi. KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Study on the Equilibrium Between Liquid Iron and Calcium Vapor2017Ingår i: Metallurgical and materials transactions. B, process metallurgy and materials processing science, ISSN 1073-5615, E-ISSN 1543-1916, Vol. 48, nr 3, s. 1715-1720Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The solubility of calcium in liquid iron at 1823 K and 1873 K (1550 A degrees C and 1600 A degrees C) as a function of calcium potential was studied experimentally. The measurements were performed using a closed molybdenum holder in which liquid calcium and liquid iron were held at different temperatures. The results indicate a linear relationship between the activity of calcium, relative to pure liquid calcium, and the mole fraction of dissolved calcium in liquid iron, with a negligible temperature dependency in the ranges studied. The activity coefficient of calcium in liquid iron at infinite dilution, was calculated as 1551.

  • 4.
    Berg, Martin
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Sichen, Du
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Effect of Aluminum on the Solubility of Calcium in Liquid Iron at Low Calcium and Aluminum Contents2020Ingår i: ISIJ International, ISSN 0915-1559, E-ISSN 1347-5460, Vol. 60, nr 1, s. 190-192Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The solubility of calcium in liquid iron as a function of aluminum content and calcium potential, at compositions relevant to production of aluminum killed steels, was studied experimentally at 1 873 K. The measurements were made using a closed molybdenum chamber in which iron-aluminum alloys were held. The calcium potential was fixed using pure liquid calcium held at different temperatures. The calcium contents in the iron varied between 6 and 22 ppm by weight and the aluminum contents varied between 70 and 1 900 ppm by weight. The results indicate that the effect of aluminum on the solubility of calcium in iron is very low in the composition ranges studied.

  • 5.
    Huss, Joar
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Berg, Martin
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Kojola, Niklas
    SSAB AB, Grp Res & Innovat, Box 70, S-10121 Stockholm, Sweden..
    Experimental Study on Phosphorus Partitions Between Liquid Iron and Liquid Slags Based on DRI2020Ingår i: Metallurgical and materials transactions. B, process metallurgy and materials processing science, ISSN 1073-5615, E-ISSN 1543-1916, Vol. 51, nr 2, s. 786-794Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Phosphorus partition between liquid iron and CaO-SiO2-MgO-FeOx slags have been investigated experimentally. Fe doped with Fe3P was equilibrated, at 1873 K, in a closed system, with a fully liquid, MgO saturated slag in a dense-sintered MgO crucible. Synthetic slags with low CaO/SiO2 ratio (1 to 1.32) and varying FeOx concentrations (10 to 30 wt pct) constituted the slag phase. P2O5 concentrations in the slag varied between 0.3 and 1.5 wt pct for added phosphorus concentrations of 0.06 to 0.316 wt pct. Phosphorus partition has been found to increase with increasing CaO/SiO2 ratios. Phosphorus partition increased with increasing oxygen potential over the investigated oxygen partial pressure range, pO2=1.4x10-5to4.8x10-5(Pa). The present experimental result has been compared with literature data. The effect of slag basicity on the dephosphorization power of slags has been discussed based on this comparison. The minimum amount of slag to achieve sufficient dephosphorization using DRI has also been calculated and discussed.

  • 6. Lindvall, M.
    et al.
    Berg, Martin
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Sichen, Du
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    The Effect of Al2O3, CaO and SiO2 on the Phase Relationship in FeO-SiO2 Based Slag with 20 Mass% Vanadium2017Ingår i: Journal of Sustainable Metallurgy, ISSN 2199-3823, Vol. 3, nr 2, s. 289-299Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    An innovative and sustainable way for production of vanadium (V) is to co-process V titanomagnetite ores with V-bearing steel slag, via reduction. V-slag produced from highly enriched Fe-V melt contains as high as 20 mass% V. The phase relationship in FeO-SiO2 based slag with V fixed at 20.4 mass% was investigated experimentally at 1673 K. The compositions covered the normal production range, viz. Al2O3 from 0 to 6 mass%, CaO from 1 to 5 mass% and SiO2 from 10 to 17 mass%. The content of MnO was fixed at 5.5 mass%. Samples quenched at 1673 K were found to be solid-liquid mixtures, either in a 2-phase region consisting of liquid and a solid spinel phase, or in 3-phase region consisting of liquid, spinel phase and silica phase. Free silica was only found in samples with a composition of 0 mass% Al2O3, 1 mass% CaO and 17 mass% SiO2. Formation of free silica was prohibited in samples with 1 mass% CaO and up to 17 mass% SiO2 by adding 5 mass% Al2O3. Addition of 4 mass% Al2O3 was also sufficient to prevent the presence of free silica in samples with 3 mass% CaO and 13.5 mass% SiO2. Most of the V was kept in the spinel phase, while the solubility of V in the liquid was generally less than 1 mass% as V2O3. Fe, Mn and Al coexisted in both liquid phase and spinel phase. On the other hand, Si and Ca only distributed in the liquid phase. The fraction of solid phase, viz. spinel was found to decrease with increasing SiO2 content.

    Ladda ner fulltext (pdf)
    fulltext
  • 7. Lindvall, M.
    et al.
    Tikka, J.
    Berg, M.
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg.
    Ye, G.
    Sichen, D.
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg.
    Vanadium Extraction from a Fe–V (2.0 Mass%)–P (0.1 Mass%) Melt and Investigation of the Phase Relations in the Formed FeO–SiO 2 -Based Slag with 20 Mass% V2017Ingår i: Journal of Sustainable Metallurgy, ISSN 2199-3823, Vol. 3, nr 4, s. 808-822Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    An innovative and sustainable way for production of vanadium is to co-process vanadium titanomagnetite ores with vanadium-bearing slag from steel industry, via reduction, producing a hot metal containing about 2 mass% vanadium, 0.1 mass% phosphorus, and 0.4 mass% silicon. A vanadium-extraction method was developed for these hot metals using a semi-industrial-scale converter. Oxidation was carried out with an air jet enriched to 50 vol% oxygen and by top-charging up to 70 kg iron ore pellets per ton hot metal. The complete dissolution of pellets was achieved by deliberately creating good stirring conditions utilizing high momentary decarburization rates. The temperature could be controlled to around 1677 K at the blowing endpoint after the pellet coolant had been dissolved. Produced vanadium slags contained as high as 20 mass% V. The semifinished product contained about 3 mass% carbon and 0.1 mass% vanadium, corresponding to a vanadium yield of 94%. The phosphorus distribution to the slag was low when good stirring was maintained. The slag composition had a more significant impact than the temperature on the vanadium distribution. Laboratory-scale study also showed that the temperature impact on the composition of the liquid phase was minor. 

  • 8.
    Lindvall, Mikael
    et al.
    Swerea MEFOS.
    Tikka, Janne
    Pöyry.
    Berg, Martin
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Ye, Guozhu
    Swerea MEFOS.
    Sichen, Du
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Vanadium extraction from a Fe-V(2.0mass%)-P(0.1mass%) melt and investigation of the phase relations in the formed FeO-SiO2 based slag with 20mass% V2017Ingår i: Journal of sustainable metallargy, ISSN 2199-3823Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    An innovative and sustainable way for production of vanadium is to co-process vanadium titanomagnetite ores with vanadium bearing slag from steel industry, via reduction, producing a hot metal containing about 2mass% vanadium, 0.1mass% phosphorus and 0.4mass% silicon. A V extraction method was developed for these hot metals using a semi-industrial scale converter. Oxidation was carried out with an air jet enriched to 50vol% oxygen and by top-charging up to 70kg iron ore pellets per ton hot metal. The complete dissolution of pellets was achieved by deliberately creating good stirring conditions utilizing high momentary decarburization rates. The temperature could be controlled to around 1677K at the blowing endpoint after the pellet coolant had been dissolved. Produced vanadium slags contained as high as 20mass% V. The semi-finished product contained about 3mass% carbon and 0.1mass% vanadium, corresponding to a vanadium yield of 94%. The phosphorus distribution to the slag was low when good stirring was obtained. The slag composition had a more profound impact than the temperature on the vanadium distribution. Laboratory scale study also showed that the temperature impact on the fraction of the solid spinel phase and on the composition of the liquid phase are low and could explain this statement.

1 - 8 av 8
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf