The Thermal Insulation of Aluminium Electrolytic Cells

Victor C. Pandolfelli1, Paschoal Bonadia2, Jorge B. Gallo3

1 Federal University of São Carlos, Materials Engineering Department, São Carlos, SP, Brazil
2 Magnesita Refratários S.A., Research and Development Center, Contagem, MG, Brazil, E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.
3 Alcoa Alumínio S.A., Applications and Development Department, Poços de Caldas, MG, Brazil, E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Revision

Volume 1, Issue 2, Pages 132 - 139

Abstract

TThe working life of aluminium electrolytic cells are markedly affected by their refractory lining. For that reason, smelters all around the world have teams of specialists who are in charge of designing and selecting the proper materials for pot lining, aiming at longer campaigns.This, however, is not a straightforward task, since the operational practices in the pot room are becoming increasingly more aggressive in order to attain higher productivity. The thermal insulation, which is part of the cathode-bottom lining, plays a major role in the cell´s heat balance, thus affecting its performance. There are a number of insulating materials available in the market, however, selecting the right one for a given pot design is not as simple as it may seem. The most suitable insulation is the one that places the critical isothermal lines (800 – 850 °C) in the right level of the lining and is able to withstand the load of the cathode blocks and barrier bricks without creeping. Some laboratory tests, such as the refractoriness under load and the thermal conductivity, have proved to be of great help to assess the quality and the performance of materials from different sources before moving to high cost industrial trials.he working life of aluminium electrolytic cells are markedly affected by their refractory lining. For that reason, smelters all around the world have teams of specialists who are in charge of designing andselecting the proper materials for pot lining, aiming at longer campaigns. This, however, is not a straightforward task, since the operational practices in the pot room are becoming increasingly more aggressive in order to attain higher productivity. The thermal insulation, which is part of the cathode-bottom lining, plays a major role in the cell´s heat balance, thus  affecting its performance. There are a number of insulating materials available in the market, however, selecting the right one for a given pot design is not as simple as it may seem. The most suitable insulation is the one that places the critical isothermal lines (800 – 850 °C) in the right level of the lining and is able to withstand the load of the cathode blocks and barrier bricks without creeping. Some laboratory tests, such as the refractoriness under load and the thermal conductivity, have proved to be of great help to assess the quality and the performance of materials from different sources before moving to high cost industrial trials.

Keywords

aluminium, pot lining, refractory, thermal insulation

References

Copyright

© 2010 Göller Verlag