Abstract
An electric potential probe was constructed so that simultaneous, multiple measurements of electric potential could be made in a six-in-line electric furnace for smelting nickel calcine having a maximum transformer capacity of 36 MVA. When the electric potential distributions were compared with those calculated from the solution of the Laplace equation, it was evident that there was significant electric potential drop at the electrode surface, 100 to 120 V for an applied potential of 180 to 230 V and currents of 20 to 30 kA. The Soderberg electrodes were continuously oxidized in the slag, likely creating carbon monoxide. The electric potential drop at the surface was attributed to arcing through the carbon monoxide. Thus, heat was released in the immediate vicinity of the electrode due to arcing, as well as in the bulk of the slag by Joule heating. The proper distribution of heat dissipation is required for the transport model, developed in Part II of this series.
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Abbreviations
- f g :
-
geometric factor of the electric furnace (l/m)
- H e :
-
electrode immersion in slag (m)
- H s :
-
slag thickness (m)
- I :
-
electrical current (A)
- J :
-
conduction current density (A/m2)
- L :
-
length scale (m)
- R e :
-
extra resistance between slag and electrode (ohm)
- R s :
-
resistance of slag alone (ohm)
- Re m :
-
magnetic Reynolds number, LU/α m (—)
- V c :
-
electric potential applied to electrode (V)
- V s :
-
electric potential applied to slag (V)
- U :
-
velocity scale (m/s)
- α m :
-
magnetic diffusivity 1/σ s μ m
- σ s :
-
electrical conductivity of slag (mho/m)
- μ m :
-
magnetic permeability (Henry/m)
References
A.G. Matyas, R.C. Francki, K.M. Donaldson, and B. Wasmund: CIM Bull., 1993, vol. 86 (972), pp. 92–99.
J.C. Taylor and H.R. Traulsen: World Survey of Nonferrous Smelters, Proc. Symp. on World Survey of Nonferrous Smelters at the TMS-AIME Annual Meeting, Jan. 25–29, 1988, Phoenix, AZ.
C. Diaz, B.R. Conard, C.E. O’Neill, and A.D. Dalvi: CIM Bull., 1994, vol. 87 (98), pp. 62–68.
Y.Y. Sheng, G.A. Irons, and D.G. Tisdale: Metall. Mater. Trans. B, 1998, vol. 29B, pp. 85–94.
S.S. Attwood: Electric and Magnetic Fields, John Wiley & Sons, New York, NY, 1949, pp. 88 and 160.
J.A. Perssan and D.G. Treilhard: J. Met., 1973, Jan., pp. 34–39.
R.C. Urquhart, M.S. Rennie, and C.C. Rabey: Proc. Int. Symp. on Copper Extraction and Refining, Feb. 22–26, 1976, Las Vegas, NV, A.K. Biswas and W.G. Davenport, eds., TMS-AIME, Warrendale, PA, 1976.
Q. Jiao and N.J. Themelis: Metall. Trans. B, 1988, vol. 19B, pp. 133–40.
G. O’Connell: “Relationship between Slag Depth, Electrode Immersion, and Electrode Resistance in Falconbridge’s Electric Furnaces,” Inter-office Technical Report, Metallurgical Technology Centre. Falconbridge, Sudbury, ON, Canada, May 31, 1993.
Q. Jiao and N.J. Themelis: Metall. Trans. B, 1991, vol. 22B, pp. 183–92.
N.M. Stubina, G.H. Kaiura, H. Tseng, and J.M. Toguri: “To Develop a Clean Smelting Process for Highly Roasted Copper-Nickel Calcines and to Improve Metal Recovery, Part D: Electrical Conductivity Measurements of Electric Furnace Smelting Slags,” DSS File No. 15SQ.23440-3-9172, University of Toronto, Toronto, 1988.
N. Stubina, J. Chao, and C. Tan: CIM Bull., 1994, June, pp. 57–61.
J.D. Kraus and K.R. Carver: Electromagnetics, 2nd ed. McGraw-Hill Book Company, New York, NY, 1973.
W.F. Hughes and F.J. Young: The Electromagnetodynamics of Fluids, Wiley, New York, NY, 1966.
J.R. Jones, M.A. Laughton, and M.G. Say: Electrical Engineer’s Reference Book, 15th ed., Butterworth-Heinemann Ltd., Oxford, United Kingdom, 1993.
R. Jones: Mintek, Randburg, South Africa, private communication, 1996.
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Sheng, Y.Y., Irons, G.A. & Tisdale, D.G. Transport phenomena in electric smelting of nickel matte: Part I. Electric potential distribution. Metall Mater Trans B 29, 77–83 (1998). https://doi.org/10.1007/s11663-998-0009-y
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DOI: https://doi.org/10.1007/s11663-998-0009-y