Because of the increasingly prominent problem of alumina content inhomogeneity in large or super-scale aluminum reduction cells, a transient numerical model for the alumina mixing process was developed for a 400 kA cell, and the relationship between the alumina content distribution and electrolyte flow field was analyzed. In the ANSYS software platform, several numerical simulation cases were presented to display the influence of the feeder configuration on the alumina mixing characteristics. The results showed that a large vortex flow of the molten electrolyte is beneficial for alumina mixing and uniform distribution in the inner areas of the vortexes. The alumina particles reach the inter-electrode zone in 10?15 s from the beginning of the feeding action, and the risk of early precipitation occurs in 10?25 s after the feeding. It was also found that a suitable grouping of feeders could reduce the content fluctuation and gradient. Therefore, a feeding on demand strategy was proposed, and the simulation results showed that although the spatial characteristics are not changed, the uniformity of the alumina content was markedly improved.%针对特大型铝电解槽内氧化铝含量不均匀性日益突出的问题,建立了铝电解槽内氧化铝输运过程的瞬态数学模型.以某400 kA铝电解槽为实例,计算分析了槽内氧化铝含量分布与电解质流动、下料系统配置的关系.结果表明,电解质的大漩涡流动有利于氧化铝在漩涡内快速输运,实现漩涡内部浓度均匀分布;氧化铝下料后10~15 s即可输运到极间,早期沉淀风险发生在下料后的10~25 s;分组交叉的下料配置可减少槽内含量波动,并一定程度上改善了含量分布的均匀性.在此基础上,提出了铝电解槽"分区按需下料"策略,尽管含量的空间分布特性未发生根本性改变,但全槽氧化铝含量分布的均匀性得到了明显的优化.
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