About this Abstract |
Meeting |
2022 TMS Annual Meeting & Exhibition
|
Symposium
|
Aluminum Reduction Technology Joint Session with REWAS: Decarbonizing the Metals Industry
|
Presentation Title |
Stabilizing Electrolysis Cells with Oscillating Currents: Amplitude, Frequency and Current Efficiency |
Author(s) |
Ibrahim Mohammad, Marc Dupuis, Paul D. Funkenbusch, Douglas H. Kelley |
On-Site Speaker (Planned) |
Ibrahim Mohammad |
Abstract Scope |
The metal pad instability (MPI) imposes a minimum electrolyte layer thickness for stable operation of aluminium electrolysis cells, which limits cells' energy efficiency. The MPI is a magnetohydrodynamic process that depends on a coupled resonance between hydrodynamic gravity wave modes, driven by the cell's electrolytic current, appearing as a circulating traveling wave that grows exponentially. Adding an oscillating current component, whose frequency is close to a low-frequency gravity mode instead excites standing waves that can prevent the MPI. Here, we show that the a minimum oscillation amplitude is required for preventing the MPI, but excessive amplitude causes a wave that shorts the cell. Proper oscillation frequency choice also impacts the stabilization effect. We also discuss the impact of exciting standing waves on the current efficiency of the cell. Applying oscillating currents could significantly increase the energy efficiency of Al cells without the need for expensive reconstruction, paving the way towards more efficient, low carbon Al production. |
Proceedings Inclusion? |
Planned: Light Metals |
Keywords |
Aluminum, Modeling and Simulation, Sustainability |