Metallurgical and Materials Transactions B

, Volume 29, Issue 1, pp 77–83 | Cite as

Transport phenomena in electric smelting of nickel matte: Part I. Electric potential distribution

  • Y. Y. Sheng
  • G. A. Irons
  • D. G. Tisdale
Article
Received:

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.

Keywords

Material Transaction Electric Furnace Molten Slag Electric Potential Distribution Nickel Laterite 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Nomenclature

fg

geometric factor of the electric furnace (l/m)

He

electrode immersion in slag (m)

Hs

slag thickness (m)

I

electrical current (A)

J

conduction current density (A/m2)

L

length scale (m)

Re

extra resistance between slag and electrode (ohm)

Rs

resistance of slag alone (ohm)

Rem

magnetic Reynolds number, LU/α m (—)

Vc

electric potential applied to electrode (V)

Vs

electric potential applied to slag (V)

U

velocity scale (m/s)

αm

magnetic diffusivity 1/σ s μ m

σs

electrical conductivity of slag (mho/m)

μm

magnetic permeability (Henry/m)

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Copyright information

© ASM International & TMS-The Minerals, Metals and Materials Society 1998

Authors and Affiliations

  • Y. Y. Sheng
    • 1
  • G. A. Irons
    • 2
  • D. G. Tisdale
    • 3
  1. 1.Noranda Technology CentrePointe ClairsCanada
  2. 2.the Department of Materials Science and EngineeringMcMaster UniversityHamiltonCanada
  3. 3.the Smelter Complex, Falconbridge LimitedFalconbridgeCanada

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