| About this Abstract |
| Meeting |
2024 TMS Annual Meeting & Exhibition
|
| Symposium
|
Aluminum Reduction Technology
|
| Presentation Title |
Limits for the Current Efficiency in Hall-Héroult Cells |
| Author(s) |
Asbjorn Solheim |
| On-Site Speaker (Planned) |
Asbjorn Solheim |
| Abstract Scope |
A chemical model for the current efficiency (CE) in aluminium cells was used for estimating the maximum attainable CE in industrial cells. The model assumes that the loss in CE is governed by mass transfer of dissolved metal from the metal surface (cathode) to the bulk of the bath. The model implies that when the CE is plotted as a function of the mass transfer coefficient at the cathode, there will be a maximum in CE. For a high-productivity cell with contemporary bath composition the maximum appears to be about 96.5 %. Some factors that lower the current efficiency are briefly discussed (too low anode-cathode distance, formation of a layer of solid matter at the cathode (metal-bath interface), polyvalent impurity elements, cathode wear, carbon particles, metal droplets, and small gas bubbles in the bath). A solid layer of cryolite and/or alumina is not necessarily detrimental for the CE. |
| Proceedings Inclusion? |
Planned: Light Metals |
| Keywords |
Aluminum, Electrometallurgy, Modeling and Simulation |