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Understanding the Anode Porosity as a Means for Improved Aluminium Smelting

  • Epma Putri
  • Geoffrey Brooks
  • Graeme A. Snook
  • Stein Rørvik
  • Lorentz Petter Lossius
  • Ingo Eick
Conference paper
Part of the The Minerals, Metals & Materials Series book series (MMMS)

Abstract

The anode pore structure affects gas diffusion as well as air and carboxy reactivity burn-off during the aluminium electrolysis. The coarse porosity was investigated using X-ray computed tomography, the mid-range porosity using optical microscopy, and the finest porosity using mercury intrusion porosimetry. These methods were combined to gain a deeper understanding of porosity and how this affects anode quality and the potential for energy savings. Test materials were received from Hydro Aluminium with different coke sources, particle sizes, binder levels, and mixing temperatures. The paper will present measurement results and link these to production and process factors. The findings indicate that direct comparison for each technique is challenging because of the physical basis of the measurement and the different measurable pore size ranges. However, the combination of different techniques gives valuable insight to understanding anode porosity. Coke type, granulometry, pitch content and baking process affecting anode porosity, properties and reactivity.

Keywords

Carbon anodes Porosity Mercury intrusion porosimetry Image analysis Computed tomography 

Notes

Acknowledgements

The present work was supported and financed by Hydro Aluminium and the Research Council of Norway. Permission to publish the results is gratefully acknowledged.

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Copyright information

© The Minerals, Metals & Materials Society 2018

Authors and Affiliations

  • Epma Putri
    • 1
    • 2
  • Geoffrey Brooks
    • 1
  • Graeme A. Snook
    • 2
  • Stein Rørvik
    • 3
  • Lorentz Petter Lossius
    • 4
  • Ingo Eick
    • 5
  1. 1.Faculty of Science, Engineering and TechnologySwinburne University of TechnologyHawthornAustralia
  2. 2.CSIRO, Mineral ResourcesClaytonAustralia
  3. 3.SINTEF Materials and ChemistryTrondheimNorway
  4. 4.Hydro AluminiumØvre ÅrdalNorway
  5. 5.Hydro Aluminium Deutschland GmbHNeussGermany

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