The Importance of Controlling Alumina Content in Electrolysis

【China Aluminum Industry Network】 Alumina is an important part of the electrolytic aluminum production process. It is necessary to perform qualitative analysis and research on the alumina content. This article will introduce the effect of alumina content on the main production parameters of electrolytic aluminum.

1. Effect of alumina content on current efficiency There are two arguments for this problem in the scientific community. One is that the alumina content is high and the current efficiency is high; the other is that the alumina content is low and the current efficiency is high. In fact, the two statements can not be wrong. Under different production conditions, sometimes the alumina content is too high, it is easy to produce precipitation and damage the electrolytic cell; sometimes the alumina content is too low, it is prone to anode effect. This mainly judges the suitability of the alumina content based on the actual matching production conditions. However, after the special large-scale pre-baking cells for aluminum electrolysis, it has been proved that the effect of low alumina content is better.

2. Effect of Alumina Content on Electrolyte The data show that the increase of alumina content will cause the electrolyte temperature to decrease, which will increase the current efficiency.

3, the impact of alumina content on the solubility of carbon dioxide in the electrolyte Practice surface, low alumina content can reduce the solubility of carbon dioxide in the electrolyte; can reduce the total area of anode bubbles, thereby reducing the amount of dissolved carbon dioxide decreases, and then reduce the secondary aluminum liquid Loss of oxidation.

4. Relationship between alumina content and alumina precipitation At present, most of the production uses low-temperature electrolysis, and the solubility of the electrolyte in the low-temperature molecular ratio of the alumina is greatly reduced, and precipitation is likely to occur. Because of the use of low alumina content, it is possible to avoid the production of a large amount of precipitation in the electrolytic cell, which is a stable operation of electrolytic production.

Alumina has more or less influence on the parameters of electrolysis production. In the production, attention should be paid to the control of the content, and the aluminum oxide content adjustment plan should be adjusted in real time according to the site conditions and the control should be well controlled.