About this Abstract |
| Meeting |
2027 TMS Annual Meeting & Exhibition
|
| Symposium
|
Aluminum Reduction Technology
|
| Presentation Title |
Cathodic Efficiency Loss in Aluminium Electrolysis: Mechanisms, Peripheral Cathodic Deposits, and Driving Forces – A Comprehensive Review |
| Author(s) |
Joseph Ndjebayi Nloga, Pierre-Luc Voyer, Francis Lalancette, Alexandre Perron, Dany Lavoie |
| On-Site Speaker (Planned) |
Joseph Ndjebayi Nloga |
| Abstract Scope |
Solid deposits along cathodic periphery in Hall–Héroult cells affect thermal balance, stability, efficiency, and cell life. This study investigates layered accumulations of corundum (α Al₂O₃), chiolite (Na₅Al₃F₁₄), and verneite phases (Na₂Ca₃Al₂F₁₄), emphasizing anode-shadowed regions and limits of pot tending machine (PTM) cleaning. Field observations, autopsies, microstructural and thermochemical characterization show that growth is driven by local supersaturation, slurry stagnation, and incomplete mechanical removal. Poor PTM-shovel reach produces thicker, stratified deposits formed by repeated redistribution of slurry from the bath center to peripheral cathodic zones. Hypotheses were tested via laboratory simulations and experiments. XRD and SEM–EDS reveal phase assemblages and compositional gradients tied to bath chemistry and temperature. Results indicate deposit evolution is not purely physicochemical but strongly controlled by mechanical constraints; shovel asymmetry promotes self-organization and feedback that sustains buildup. The findings guide improvements in cleaning efficiency, shovel design, and process control to reduce losses and extend cell life |
| Proceedings Inclusion? |
Planned: Light Metals |
| Keywords |
Aluminum, Solidification, Phase Transformations |