Numerical simulation on electrolyte flow field in 156 kA drained aluminum reduction cells

Abstract

Based on the commercial CFD software CFX-4.3, two-phase flow of electrolyte in 156 kA drained aluminum reduction cells with a new structure was numerically simulated by multi-fluid model and k-ɛ turbulence model. The results show that the electrolyte flow in the drained cells is more even than in the conventional cells. Corresponding to center point feeding, the electrolyte flow in the drained cells is more advantageous to the release of anode gas, the dissolution and diffusion of alumina, and the gradient reduction of the electrolyte density and temperature. The average velocity of the electrolyte is 8.3 cm/s, and the maximum velocity is 59.5 cm/s. The average and maximum velocities of the gas are 23.2 cm/s and 61.1 cm/s, respectively. The cathode drained slope and anode cathode distance have certain effects on the electrolyte flow.

Keywords

drained aluminum reduction cells / electrolyte / two-phase flow / numerical simulation

References

[1] MeiChi.Simulation and Optimization of the Nonferrous Metallurgy Furnaces[M], 2001, Beijing, Metallurgical Industry Press: 150-151

[2] WahnsiedlerW. E.. Hydrodynamic modeling of commercial hall-heroult cells[C]. Light Metals, 1987, Warrendale, TMS: 269-287

[3] PurdieJ. M., BilekM., TaylorM. P., et al.. Impact of anode gas evolution on electrolyte flow and mixing in aluminum electrowinning cells[C]. Light Metals, 1993, Warrendale, TMS: 355-360

[4] GaoZ.-s., LiG.-x., ShenJ.-yun.. Mathematical modeling of bubble driven flows in a novel aluminum electrolysis cell[J]. Transactions of Nonferrous Metals Society of China, 1996, 6(2): 37-40

[5] BilekM. M., ZhangW. D., StevensF. J.. Modelling of electrolyte flow and its related transport process in aluminum reduction cells[C]. Light Metals, 1994, Warrendale, TMS: 323-331

[6] ZhouL.-xing.Fluid Mechanics of Multi-phase Turbulent Reaction[M], 2002, Beijing, National Defence Industry Press: 78-101

[7] JiangC.-w., MeiC., ZhouN.-j., et al.. Computation of 3 D magnetic field in prebaked cells using scalar voltage potential method and two scalar magnetic potentials method[J]. The Chinese Journal of Nonferrous Metals, 2003, 13(4): 1021-1025

[8] ZhouN.-j., MeiC., JiangC.-w., et al.. Coupled computation method of physics fields in aluminum reduction cells[J]. Transactions of Nonferrous Metals Society of China, 2003, 13(2): 431-437

[9] ZhouZ.-ming.Thermo-Electric Coupled Simulation and Optimization of Drained Aluminum Reduction Cells[D], 2004, Changsha, School of Energy Science and Engineering, Central South University

[10] ZHOU Nai-jun, LI Jie, JIANG Chang-wei, et al. A kind of drained aluminum reduction cells with TiB₂ coating cathode. China: 200410023392.X[P]. 2004-07-06.

[11] SolheimA., JohansenS. T., RolsethS., et al.. Gas driven flow in Hall-Heroult cells[C]. Light Metals, 1989, Warrendale, TMS: 245-252

[12] KobbeltvedtO., MoxnesB. P.. On the bath flow, alumina distribution and anode gas release in aluminum cells[C]. Light Metals, 1997, Warrendale, TMS: 369-376

[13] ZoricJ., SolheimA.. On gas bubbles in industrial aluminum cells with prebaked anodes and their influence on the current distribution[J]. Journal of Applied Electrochemistry, 2000, 30: 787-794

[14] LiX.-p., LiJ., LaiY.-q., et al.. Physical modeling of gas induced bath flow in drained aluminum reduction cell[J]. Transactions of Nonferrous Metals Society of China, 2004, 14(5): 1017-1022

[15] XiaX.-xia.Numerical Simulation on the Electrolyte Flow Field of Aluminum Reduction Cells[D], 2005, Changsha, School of Energy Science and Engineering, Central South University