New Sidewall Materials in Aluminum Reduction Cell
The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, 430081Wuhan/China
Revision 20.04.2014, 18.06.2014
Volume 6, Issue 4, Pages 101 - 106
Nowadays the heat dissipating has to be reduced as far as possible in new electrolysis technology in order to meet the needs of energy saving in aluminum industry. Ledge-free sidewall is preferred as it potentially reduces the energy requirement of aluminum production and allows the use of larger anode that increase capacity and productivity of a cell of the same dimensions. Also the environmental impacts would be reduced significantly in combination with inert anodes and cathode application. However, the sidewalls are facing the extreme challenge because they will be in direct contact with oxidizing, corrosive and reducing environments for different zones in aluminum cell. This article gives an overview of the current status and latest progress of such ledge-free sidewall materials. Also, an attempt to develop novel composite materials based on MgO–NiFe2O4–TiO2 and MgO–SnO2–TiO2 system for ledge-free sidewall have been made in our laboratory. Finally, some advices on the development of the ledge-free sidewall materials in future are proposed.
sidewalls; NiFe2O4; SnO2; composite spinel; electrolyte corrosion resistance, aluminum industry
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