Possible roles of upper slag phases on the fluid dynamics of gas stirred ladles
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Fig. 4--Relationship between dissolution rate of Fe203 in acidic chloride solution and a(H20) of the solution.
and the parameter -3.63{a(H20) - 1} + log C(HC1) on the abscissa (Figures 3 and 4). As these figures clearly show, a linear relationship was detected between log R and -3.62{a(H20) - 1} + log C(HC1) for both oxides. The slope of the straight line for CuO was 0.90, while that for Fe203 was 0.94. These values are sufficiently close to unity. These findings support the assumption made in this study. Accurate determination of liquid junction potential, and thus rigorous determination of a(H § in an acidic chloride solution is impossible. By contrast, the calculation of a(H20) value from the concentration data of the component of the solution using the Robinson-Bower equation is simple and accurate, showing only a slight deviation from that experimentally determined. Therefore, when it is desirable to analyze the dissolution reactions of oxide and perhaps sulfide in acidic solutions in terms of a(H+), Eq. [7] may be useful instead of a(H§
REFERENCES 1. H. Majima and Y. Awakura: Metall. Trans. B, 1981, vol. 12B, pp. 141-47. 29 H. Majima and Y. Awakura: Extraction Metallurgy "85, IMM, London, pp. 607-27. 3. H. Majima, Y. Awakura, T. Sato, and T. Michimoto: Denki Kagaku, 1982, vol. 50, pp. 934-40. 4. K.J. Vetter: Electrochemical Kinetics, Academic Press, New York, NY, 1967, p. 46. 5. R.A. Robinson and V.E. Bower: J9 Res9 Nat. Bur. Stand., 1965, vol. 69A, pp. 365-67. 6. H. Majima, Y. Awakura, Y. Takeshima, and K. Sato: Denki Kagaku, 1984, vol. 52, pp. 800-71. 7. R.A. Robinson and R.H. Stokes: Electrolyte Solutions, 2nd ed., Butterworth Scientific Publications, 1959, appendix 8.10. 8. Kagaku Binran, Kisohen Part 2, Nihon Kagaku Kai, ed., Maruzen, Tokyo, 1975. 9. R.G. Bates, B. R. Staples, and R. A. Robinson: Anal. Chem., 1970, vol. 40, pp. 867-71. 10. H. Majima, Y. Awakura, T. Yazaki, and Y. Chikamori: Metall. Trans. B, 1980, vol. liB, pp. 209-14. 11. H. Majima, Y. Awakura, and T. Mishima: Metall. Trans. B, 1985, vol. 16B, pp. 23-30. METALLURGICAL TRANSACTIONS B
Possible Roles of Upper Slag Phases on the Fluid Dynamics of Gas Stirred Ladles D. MAZUMDAR, H. NAKAJIMA, and R. I. L. GUTHRIE The pouring of liquid steel from a furnace into a ladle, or vice versa, generally leads to uncontrolled amounts of slag carryover. Being lighter, this slag separates to form an upper phase of variable thickness and viscosity. While its insulating properties are generally beneficial for maintaining steel temperatures, its chemical characteristics are often detrimental. For instance, steel deoxidation efficiencies can be significantly lowered through chemical reduction of the iron oxide component of any carryover slag. This mass transfer reaction with residual dissolved silicon and/or alu
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