铝电解槽内铝液扩散传质过程的数值模拟  

Numerical simulation of liquid aluminum diffusion transfer process in aluminum reduction pots

作　　者：李贺松[1] 韦隆和[1] 

机构地区：[1]中南大学能源科学与工程学院,湖南长沙410083

出　　处：《轻金属》2014年第10期27-32,共6页Light Metals

基　　金：国家自然科学基金资助项目(51004115)

摘　　要：结合多相流以及湍流传质等相关理论,充分考虑湍流以及浓度边界层对传质过程的影响,引入双方程湍流传质模型封闭湍流扩散系数,建立了较为完善的铝电解槽内铝液扩散传质模型。对350kA系列槽不同磁场工况下的铝液浓度场进行数值模拟,计算结果表明:铝浓度在边界层内迅速降低,湍流区内铝浓度变化不大,在反应区内铝被阳极气体氧化,浓度显著下降;;电磁力和气泡作用力共同影响铝液扩散过程,但扩散速率主要取决于电磁力。极距间铝液浓度分布模拟结果与测试结果较为吻合,模拟电流效率损失情况与现场基本一致。因此本模型具有一定可靠性和实用性,能够为节能优化提供理论依据。Combining with multiphase flow and turbulent transfer theory, the impact of turbulent and concentration boundary layer to mass transfer process was fully considered and two - equation turbulent mass transfer model to close turbulent diffusion coefficient was introduced, then the model of liquid aluminum diffusion transfer in aluminum reduction pots was established. The aluminum concentration fields of 350kA series pots under different magnetic field conditions were simulated. The results showed that aluminum concentration decreased rapidly in the boundary layer, and was almost unchanged in turbulent zone, while decreased significantly in reaction zoon for the oxidation by anode gas; aluminum diffusion process was affected by electromagnetic force and bubble force ; but diffusion rate mainly depended on the electromagnetic force. The numerical results of aluminum concentration distribution in ACD were excellently consistent with the test results. The simulated current efficiency loss also coincided with the field data. So the model had a certain reliability and practicality, and could provide a theoretical basis for energy saving optimization.

关 键 词：铝电解槽 扩散传质 电流效率 铝浓度 

分 类 号：TF821[冶金工程—有色金属冶金]