现代工艺条件下预焙铝电解槽破损原因及解决对策

在综合国内外研究成果的基础上，分析了现代工艺条件下预焙铝电解槽的破损原因，并提出了延长槽寿命的对策。现行电解槽由于采用低分子比电解质，电流效率显提高，但同时由于在电解槽内容易形成界面冰晶石薄膜及氧化铝沉淀，使得钠的析出显增加，增强了钠对阴极碳块的渗透，从而导致阴极碳块膨胀破损的机率增加，为此，必须改善电解槽阴极内衬材料以延长电解槽寿命。采用半石墨化或石墨（化）阴极内衬，或在普通碳块上增加TiB2涂，可以实现上述目的。半石墨化或石墨化阴极内衬具有较好的抗钠膨胀性能，但由于石墨质软，机械磨损大且成本高，而TiB2涂层碳块阴极内衬既具有优良的抗钠爰胀和对铝润湿性能，又有良好的耐磨性，有很好的发展前景。

Failure of Pre-baking Al Electrolytic Cells Under Modern Technical Conditions--Causes and Solutions

Based on domestic and foreign resenrch results, the authors analyse the causes of failure of pre baking Al electrolytic cells under modern technical conditions and give the solutions to prolongation of their sevice life. In electrolytic cells currently in use, low modecule ratio electrolyte is used, resulting in a dramatic increase in current efficiency. At the same time, since it is easy to form cryolite film and aluminium oxide precipitate on the interface within the cells, released sodium is greatly increased, resulting in probability of expansion and breakage of cathodic carbon due to improving the penetration of sodium into cuthodic carbon. Therefore, it is necessary to improve pot lining materials, so as to prolong service life of cells. The above goals can be attained by using graphitized or semi graphitized cathodic pot lining, or by adding TiB 2 coatings onto normal carbon block. The former has better anti expansion of sodium, but it has a high mechanical wear rate and is expensive. The latter has good developing prospects due to its good anti expansion of sodium and good wettability for aluminium as well as good wear resistance.