Advertisement

Journal of Sustainable Metallurgy

, Volume 4, Issue 1, pp 3–14 | Cite as

Experimental Investigation and Modeling of the Viscosity of Oxide Slag Systems

  • M. Müller
  • S. Seebold
  • G. Wu
  • E. Yazhenskikh
  • T. Jantzen
  • K. Hack
Thematic Section: Slag Valorisation

Abstract

Numerous technical applications in the energy and metallurgical industries demand a fundamental knowledge of the flow of slags. Besides temperature and composition, which determine the internal structure of an oxide melt, crystallization in the slag significantly influences its flow behavior. Therefore, not only the temperature-dependent viscosity of fully liquid oxide melts was determined using a rotational high-temperature viscometer but also isothermal viscosity measurements were conducted, in order to examine the rheological evolution over time caused by crystallization. The crystallization behavior during flow can be separated into three time regimes: a lag-time, in which the undercooled melt behaves as an Arrhenius liquid; the kinetic-driven crystallization; and, finally, the rheological equilibrium that is represented by a time-invariant viscosity plateau. To model the viscosity of oxide slags, in a first step, a self-consistent thermodynamic database for the system SiO2–Al2O3–CaO–MgO–FeO x –K2O–Na2O–P2O5–SO x has been established. The Gibbs energy of the liquid phase has been modeled using a non-ideal associate solution description. In a second step, an Arrhenius-type model for the calculation of viscosities of fully molten slags has been developed. The model is based on the same structural units, i.e., the associates, as the one for the Gibbs energy of the melt. In a third step, the influence of crystallization, which not only transforms the liquid into dispersion but also usually changes the composition of the residual liquid, on the viscosity is considered.

Keywords

Oxide slag Viscosity Crystallization Viscosity model 

Notes

Acknowledgements

The study described in this paper has been performed within the framework of the projects: HotVeGas, supported by the Federal Ministry for Economic Affairs and Energy (FKZ 0327773); and HVIGasTech, supported by the Helmholtz Association of German Research Centres (VH-VI-429).

References

  1. 1.
    Higman C, van der Burgt M (2003) Gasification. Elsevier Science, BurlingtonGoogle Scholar
  2. 2.
    Allibert M (ed), VDEh (1995) Slag atlas 1995. Verlag Stahleisen, DusseldorfGoogle Scholar
  3. 3.
    Vargas S, Frandsen FJ, Dam-Johansen K (2001) Rheological properties of high temperature melts of coal ashes and other silicates. Prog Energy Combust Sci 27:237–429CrossRefGoogle Scholar
  4. 4.
    Browning GJ, Bryant GW, Hurst HJ, Lucas JA, Wall TF (2003) An empirical method for the prediction of coal ash slag viscosity. Energy Fuels 17:731–737CrossRefGoogle Scholar
  5. 5.
    Tinker D, Lesher CE, Baxter GM, Uchida T, Wang Y (2004) High-pressure viscometry of polymerized silicate melts and limitations of the Eyring equation. Am Mineral 89:1701–1708CrossRefGoogle Scholar
  6. 6.
    Zachariasen WH (1932) The atomic arrangement in glass. J Am Chem Soc 54:3841–3851CrossRefGoogle Scholar
  7. 7.
    Weymann HD (1962) On the hole theory of viscosity, compressibility, and expansivity of liquids. Kolloid Z Z Polym 181:131–137CrossRefGoogle Scholar
  8. 8.
    Urbain G, Bottinga Y, Richet P (1982) Viscosity of liquid silica, silicates and aluminosilicates. Geochim Cosmochim Acta 46:1061–1072CrossRefGoogle Scholar
  9. 9.
    Riboud PV, Roux Y, Lucas D, Gayes H (1981) Improvement of continuous casting powders. Fachber Huttenprax Metallweiterverarb 19:859–869Google Scholar
  10. 10.
    Kalmanovitch DP, Frank M (1988) An effective model of viscosity for ash deposition phenomena. In: Proceedings of the engineering foundation conference on mineral matter and ash deposition from coal. Santa Barbara, pp 89–101Google Scholar
  11. 11.
    Hurst HJ, Novak F, Patterson JH (1999) Viscosity measurements and empirical predictions for fluxed Australian bituminous coal ashes. Fuel 78:1831–1840CrossRefGoogle Scholar
  12. 12.
    Kondratiev A, Jak E (2001) Review of experimental data and modeling of the viscosities of fully liquid slags in the Al2O3–CaO–‘FeO’–SiO2 system. Metall Mater Trans B 32:1015–1025CrossRefGoogle Scholar
  13. 13.
    Zhang L, Jahanshahi S (1998) Review and modeling of viscosity of silicate melts: part I. Viscosity of binary and ternary silicates containing CaO, MgO, and MnO. Metall Mater Trans B 29:177–186CrossRefGoogle Scholar
  14. 14.
    Kondratiev A, Jak E (2005) A quasi-chemical viscosity model for fully liquid slags in the Al2O3–CaO–‘FeO’–SiO2 system. Metall Mater Trans B 36:623–638CrossRefGoogle Scholar
  15. 15.
    Grundy AN, Liu H, Jung IH, Decterov SA, Pelton AD (2008) A model to calculate the viscosity of silicate melts part I: viscosity of binary SiO2–MeOx systems (Me = Na, K, Ca, Mg, Al). Int J Mater Res 99:1185–1194CrossRefGoogle Scholar
  16. 16.
    Kim WY, Pelton AD, Decterov SA (2012) A model to calculate the viscosity of silicate melts part III: modification for melts containing alkali oxides. Int J Mater Res 103:313–328CrossRefGoogle Scholar
  17. 17.
    Nentwig T, Kondratiev A, Yazhenskikh E, Hack K, Müller M (2013) Viscosity model for oxide melts relevant to coal ash slags based on the associate species thermodynamic model. Energy Fuel 27:6469–6476CrossRefGoogle Scholar
  18. 18.
    Avramov I, Rüssel C, Keding R (2003) Effect of chemical composition on viscosity of oxide glasses. J Non Cryst Solids 324:29–35CrossRefGoogle Scholar
  19. 19.
    Nowok JW, Hurley JP, Stanley DC (1993) Local structure of a lignitic coal ash slag and its effect on viscosity. Energy Fuels 7:1135–1140CrossRefGoogle Scholar
  20. 20.
    Ilyushechkin AY, Hla SS, Roberts DG, Kinaev NN (2011) The effect of solids and phase compositions on viscosity behaviour and TCV of slags from Australian bituminous coals. J Non Cryst Solids 357:893–902CrossRefGoogle Scholar
  21. 21.
    Song W, Tang L, Zhu X, Wu Y, Zhu Z, Koyama S (2010) Flow properties and rheology of slag from coal gasification. Fuel 89:1709–1715CrossRefGoogle Scholar
  22. 22.
    Oh MS, Brooker DD, de Paz EF, Brady JJ, Decker TR (1995) Effect of crystalline phase formation on coal slag viscosity. Fuel Process Technol 44:191–199CrossRefGoogle Scholar
  23. 23.
    Nowok JW (1994) Viscosity and phase transformation in coal ash slags near and below the temperature of critical viscosity. Energy Fuels 8:1324–1336CrossRefGoogle Scholar
  24. 24.
    Song W, Sun Y, Wu Y, Zhu Z, Koyama S (2011) Measurement and simulation of flow properties of coal ash slag in coal gasification. AIChE J 57:801–818CrossRefGoogle Scholar
  25. 25.
    Groen JC, Brooker DD, Welch PJ, Oh MS (1998) Gasification slag rheology and crystallization in titanium-rich, iron–calcium–aluminosilicate glasses. Fuel Process Technol 56:103–127CrossRefGoogle Scholar
  26. 26.
    Kong L, Bai J, Li W, Wen X, Li X, Bai Z, Guo Z, Li H (2015) The internal and external factor on coal ash slag viscosity at high temperatures, Part 1: effect of cooling rate on slag viscosity, measured continuously. Fuel 158:968–975CrossRefGoogle Scholar
  27. 27.
    Song WJ, Tang L, Zhu Z, Ninomiya Y (2013) Rheological evolution and crystallization response of molten coal ash slag at high temperatures. AIChE J 59:2726–2742CrossRefGoogle Scholar
  28. 28.
    Wright S, Zhang L, Sun S, Jahanshahi S (2000) Viscosity of a CaO-MgO-Al2O3-SiO2 melt containing spinel particles at 1646 K. Metall Mater Trans 31:97–104CrossRefGoogle Scholar
  29. 29.
    Wright S, Zhang L, Sun S, Jahanshahi S (2001) Viscosities of calcium ferrite slags and calcium alumino-silicate slags containing spinel particles. J Non Cryst Solids 282:15–23CrossRefGoogle Scholar
  30. 30.
    Mezger TG (2012) Das Rheologie Handbuch. Vincentz, HannoverGoogle Scholar
  31. 31.
    Mills KC, Franken M, Machingawuta N, Green P, Broadbent C, Urbain G, Scheel R, Hocevior J, Pontoire JN (1991) Commision report on standard reference material (SRM) for high temperature viscosity measurements. NPL Report DMM(A) 30, NPL, Teddington, UKGoogle Scholar
  32. 32.
    Seebold S, Wu G, Müller M (2017) The influence of crystallization on the flow of coal ash-slags. Fuel 187:376–387CrossRefGoogle Scholar
  33. 33.
    Kouchi A, Tsuchiyama A, Sunagawa I (1986) Effect of stirring on crystallization kinetics of basalt: texture and element partitioning. Contrib Miner Petrol 93:429–438CrossRefGoogle Scholar
  34. 34.
    Wu G, Yazhenskikh E, Hack K, Wosch E, Müller M (2015) Viscosity model for oxide melts relevant to fuel slags. Part 1: pure oxides and binary systems in the system SiO2-Al2O3-CaO-MgO-Na2O-K2O. Fuel Process Technol 137:93–103CrossRefGoogle Scholar
  35. 35.
    Wu G, Yazhenskikh E, Hack K, Müller M (2015) Viscosity model for oxide melts relevant to fuel slags. Part 2: the system SiO2-Al2O3-CaO-MgO-Na2O-K2O. Fuel Process Technol 138:520–533CrossRefGoogle Scholar
  36. 36.
    Yazhenskikh E, Hack K, Müller M (2006) Critical thermodynamic evaluation of oxide systems relevant to fuel ashes and slags. Part 1: alkali oxide–silica systems. Calphad 30:270–276CrossRefGoogle Scholar
  37. 37.
    Yazhenskikh E, Hack K, Müller M (2006) Critical thermodynamic evaluation of oxide systems relevant to fuel ashes and slags. Part 2: alkali oxide–alumina systems. Calphad 30:397–404CrossRefGoogle Scholar
  38. 38.
    Yazhenskikh E, Hack K, Müller M (2008) Critical thermodynamic evaluation of oxide systems relevant to fuel ashes and slags. Part 3: silica–alumina systems. Calphad 32:195–205CrossRefGoogle Scholar
  39. 39.
    Yazhenskikh E, Hack K, Müller M (2008) Critical thermodynamic evaluation of oxide systems relevant to fuel ashes and slags. Part 4: sodium oxide–potassium oxide–silica. Calphad 32:506–513CrossRefGoogle Scholar
  40. 40.
    Yazhenskikh E, Hack K, Müller M (2011) Critical thermodynamic evaluation of oxide systems relevant to fuel ashes and slags, Part 5: potassium oxide–alumina–silica. Calphad 35:6–19CrossRefGoogle Scholar
  41. 41.
    Yazhenskikh E, Jantzen T, Hack K, Müller M (2014) Critical thermodynamic evaluation of oxide systems relevant to fuel ashes and slags: potassium oxide–magnesium oxide–silica. Calphad 47:35–49CrossRefGoogle Scholar
  42. 42.
    Jantzen T, Hack K, Yazhenskikh E, Müller M (2017) Evaluation of thermodynamic data and phase equilibria in the System Ca-Cr-Cu-Fe-Mg-Mn-S Part I: binary and quasi-binary subsystems”. Calphad 56:270–285CrossRefGoogle Scholar
  43. 43.
    Jantzen T, Hack K, Yazhenskikh E, Müller M (2017) Evaluation of thermodynamic data and phase equilibria in the System Ca-Cr-Cu-Fe-Mg-Mn-S Part I: ternary and quasi-ternary subsystems. Calphad 56:286–302CrossRefGoogle Scholar
  44. 44.
    Sundman B, Agren J (1981) A regular solution model for phases with several components and sublattices, suitable for computer applications. J Phys Chem Solids 42:297–301CrossRefGoogle Scholar
  45. 45.
    Lukas HL, Fries S, Sundman B (2007) Computational thermodynamics: the Calphad method. Cambridge University Press, New YorkCrossRefGoogle Scholar
  46. 46.
    Besmann TM, Spear KE (2002) Thermodynamic modelling of oxide glasses. J Am Ceram Soc 85:2887–2894CrossRefGoogle Scholar
  47. 47.
    Olivier L, Yuan X, Cormack AN, Jäger C (2001) Combined 29Si double quantum NMR and MD simulation studies of network connectivities of binary Na2O·SiO2 glasses: new prospects and problems. J Non-Cryst Solids 293–295:53–66CrossRefGoogle Scholar
  48. 48.
    Halter WE, Mysen BO (2004) Melt speciation in the system Na2O–SiO2. Chem Geol 213:115–123CrossRefGoogle Scholar
  49. 49.
    Maekawa H, Maekawa T, Kawamura K, Yokokawa T (1991) The structural groups of alkali silicate glasses determined from 29Si MAS-NMR. J Non-Cryst Solids 127:53–64CrossRefGoogle Scholar
  50. 50.
    Bockris JOM, Mackenzie JD, Kitchener JA (1955) Viscous flow in silica and binary liquid silicates. Trans Faraday Soc 51:1734–1748CrossRefGoogle Scholar
  51. 51.
    Elyutin VP, Kostikov VI, Mitin BS, Nagibin YA (1969) Measurements of viscosity of aluminium oxide. Zh Fiz Khim 43:579–583Google Scholar
  52. 52.
    Kozakevitch P (1960) Viscosite et elements structuraux des alumino-silicates fondus: leitiers CaO–Al2O3–SiO2 entre 1600 et 2000 °C. Rev Metall Paris 57:149–160CrossRefGoogle Scholar
  53. 53.
    Urbain G, Bottinga Y, Richet P (1982) Viscosity of liquid silica, silicates and aluminosilicates. Geochim Cosmochim Acta 46:1061–1072CrossRefGoogle Scholar
  54. 54.
    Paek UC, Schroeder CM, Kurkjian CR (1988) Determination of the viscosity of high silica glasses during fibre drawing. Glass Technol 29:263–266Google Scholar
  55. 55.
    Stein DJ, Spera FJ (1993) Experimental rheometry of melts and supercooled liquids in the system NaAlSiO4–SiO2: implications for structure and dynamics. Am Miner 78:710–723Google Scholar
  56. 56.
    Sakka S, Kamiya K, Kato N (1981) Viscosities of mixed alkali aluminosilicate glasses of the system Li2O–Na2O–Al2O3–SiO2. Res Rep Fac Eng Mie Univ 6:81–92Google Scholar
  57. 57.
    Kim KD (1995) Viscosity in mixed-alkali alumino-silicate glass melts. In: Proceedings of the XVIIth international congress on glass. Beijing, pp 747–752Google Scholar
  58. 58.
    Skornyakov MM, Kuznetsov AY, Evstropiev KS (1941) Viscosity of the system Na2SiO3–SiO2 in molten state. Zh Fiz Khim 15:116–124Google Scholar
  59. 59.
    Volarovich MP (1933) Investigation of viscosity and plasticity of molten slags and rocks. Zh Fiz Khim 4:807–814Google Scholar
  60. 60.
    Volarovich MP (1934) Investigation of viscosity of melted rocks. Dokl Akad Nauk SSSR 1:561–563Google Scholar
  61. 61.
    Cranmer D, Uhlmann DR (1981) Viscosities in the system albite–anorthite. J Geophys Res 86:7951–7956CrossRefGoogle Scholar
  62. 62.
    Semik IP (1941) On the viscosity of blast-furnace slags. In: Soveshchanie po Vyazkosti Zhidkostei i Kolloidnykh Rastvorov. Moskva, pp 257–269Google Scholar
  63. 63.
    Kolmogorov AN (1937) On the statistics of the crystallization process in metals. Bull Akad Sci USSR Class Sci Math Nat 1:355–359Google Scholar
  64. 64.
    Avrami M (1940) Kinetics of phase change. II Transformation-time relations for random distribution of nuclei. J Chem Phys 8:212–224CrossRefGoogle Scholar
  65. 65.
    Einstein A (1911) Berichtigung zu meiner Arbeit: Eine neue Bestimmung der Moleküldimensionen. Ann Phys 339:591–592CrossRefGoogle Scholar
  66. 66.
    Roscoe R (1952) The viscosity of suspensions of rigid spheres. Br J Appl Phys 3:267CrossRefGoogle Scholar
  67. 67.
    Ostwald W, De Waele A (1923) Oil and color. Chem Assoc J 6:23–24Google Scholar

Copyright information

© The Minerals, Metals & Materials Society 2017

Authors and Affiliations

  • M. Müller
    • 1
  • S. Seebold
    • 1
  • G. Wu
    • 1
  • E. Yazhenskikh
    • 1
  • T. Jantzen
    • 2
  • K. Hack
    • 2
  1. 1.Forschungszentrum Jülich GmbHInstitute of Energy and Climate Research, IEK-2JülichGermany
  2. 2.GTT-TechnologiesHerzogenrathGermany

Personalised recommendations