About this Abstract |
Meeting |
2022 TMS Annual Meeting & Exhibition
|
Symposium
|
Primary Aluminum Industry - Energy and Emission Reductions: An LMD Symposium in Honor of Halvor Kvande
|
Presentation Title |
Reflections on the Low Voltage Anode Effect in Aluminium Electrolysis Cells |
Author(s) |
Asbjorn Solheim |
On-Site Speaker (Planned) |
Asbjorn Solheim |
Abstract Scope |
The paper addresses the basic mechanisms leading to the low voltage anode effect (LVAE) as well as the high voltage anode effect (HVAE) in aluminium electrolysis cells. The root cause of any anode effect is too low alumina concentration at the anode surface. By statistical treatment based on a Gaussian distribution of the alumina concentration, it was found that the onset of a HVAE takes place at higher average concentration if there is a large standard deviation. By calculating the anode potential, it was found that an LVAE can take place at a part of the anode as small as 0.001 m2 while the rest of the anode works normally, which makes the LVAE extremely difficult to discover. It was suggested that the on-and-off current pattern observed during LVAE can be explained by alternation between blocking of the surface (AE) and normal electrolysis, induced by non-stationary mass transfer of alumina. |
Proceedings Inclusion? |
Planned: Light Metals |
Keywords |
Aluminum, Modeling and Simulation, Electrometallurgy |