State-of-the-art alumino-silicate refractories for al electrolysis cells

  • Ole-Jacob Siljan
  • Christian Schoning
  • Tor Grande
Overview Aluminum Production

Abstract

The refractory material of choice for aluminum cell bottom linings worldwide is alumino-silicates, due to high availability, relatively low cost, and empirically good performance. During operation of aluminum electrolysis cells, the alumino-silicates are subjected to infiltration and attack by molten electrolyte components. The penetration of sodium and molten fluorides through the cathode causes significant mineralogical transformation in the refractory, and, in extreme situations, it may terminate the pot life. This paper reviews the current understanding of deterioration mechanisms for refractory materials used in bottom lining of aluminum reduction cells. The silica content of the alumino-silicate refractories is the major single factor affecting deterioration rates through the formation of viscous melts and a glass-like barrier in the reacted lining. In addition, reactions between metallic sodium and alumino-silicate refractories may cause volume expansions in the exposed lining. The present review concludes that firebricks with an optimum silica content are probably still the best penetration barriers available.

Keywords

Nepheline Silica Content Solidus Temperature Refractory Material Cryolite 
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.
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Copyright information

© The Minerals, Metals & Materials Society 2002

Authors and Affiliations

  • Ole-Jacob Siljan
    • 1
    • 4
  • Christian Schoning
    • 2
  • Tor Grande
    • 3
  1. 1.Norsk Hydro ASAResearch Centre PorsgrunnUSA
  2. 2.SINTEF Materials TechnologyUSA
  3. 3.Department of ChemistryNorwegian University of Science and TechnologyUSA
  4. 4.Norsk Hydro ASAResearch Centre PorsgrunnTrondheimNorway

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