过热度对氧化铝溶解行为的影响

Effect of superheat on the dissolution behavior of alumina

电解质过热度控制和氧化铝质量分数控制对电解槽稳定生产非常重要.本文设计了一种新型透明槽(双温区透明槽),观测了载氟中间状氧化铝和砂状氧化铝在NaF-AlF 3-Al 2O 3-CaF 2-MgF 2-KF-LiF熔盐体系中的溶解行为,研究了过热度对氧化铝溶解行为的影响.研究结果表明:载氟中间状氧化铝的平均溶解速率受电解质组成和过热度影响较大,低过热度和高氧化铝质量分数都不利于载氟中间状氧化铝的溶解;电解质过热度对砂状氧化铝的溶解速率影响较小,砂状氧化铝的平均溶解速率在不同过热度的电解质中基本接近.

It is important to control electrolyte superheat and alumina mass fraction for stable production of reduction cells.In this paper,a new type of transparent cell(two-zone transparent cell)was designed to investigate the dissolution behavior of secondary intermediate alumina and sandy alumina in NaF-AlF 3-Al 2O 3-CaF 2-MgF 2-KF-LiF molten salt system.Meanwhile,the effect of superheat of aluminum electrolyte on the dissolution behavior of alumina was investigated.The results show that the dissolution behavior of secondary intermediate alumina is greatly affected by electrolyte composition and superheat.Low superheat and high alumina mass fraction have negative effects on secondary intermediate alumina dissolution rate.Electrolyte superheat has little effect on dissolution rate of sandy alumina,whose average value varies little in different superheat electrolytes.