Anode covering material for aluminum electrolysis

Abstract

The invention relates to an anode covering material for aluminum electrolysis. The material comprises the following components of, by mass, 35-40% of aluminum oxide, 18-25% of aluminum fluoride, 35-47% of a mixture of sodium fluoride and calcium fluoride, wherein the mass ratio of the anode covering material with the particle size of 10-50 mm to the particle size less than 10 mm is 3 to 2. According to the material, the anode covering material for the aluminum electrolysis can improve the conductivity of aluminum electrolyte so as to promote the bonding and curing of the fluorine-containing solid particles.

Description

technical field [0001] The invention relates to an anode covering material for aluminum electrolysis. Background technique [0002] Anode covering is an important process in the aluminum electrolysis process. The quality of this process is of great significance to the stable and efficient operation of the aluminum electrolytic cell. To ensure the quality of the anode covering operation, it is necessary not only to strengthen on-site production management, but also to ensure the performance of the anode covering material , a suitable anode covering material can achieve the following functions: [0003] (1) Reduce the heat loss of the upper part of the electrolyzer, ensure the thermal balance of the electrolyzer, and reduce the energy consumption of the electrolyzer; [0004] (2) Reduce anodic oxidation and reduce anode consumption; [0005] (3) Maintain proper temperature of electrolyte, anode carbon block, steel claw and guide rod, and reduce anode pressure drop; [0006]...

AI Technical Summary

Problems solved by technology

[0009] (1) In actual production, the blocky material (diameter range is generally 80~100mm) in the covering material will cause the blockage of the material conveying high-level silo in the aluminum electrolysis workshop and the conveying system of the aluminum electrolysis multifunctional unit, thus making the The covering material conveying system of most electrolytic aluminum enterprises is in a semi-paralyzed or paralyzed state;

[0010] (2) In the actual application process, due to the single discharge of aluminum electrolytic cell, the discharge port is accompanied by the phenomenon of fluorine-loaded alumina material floating, which will cause the fluorine-loaded alumina that has not entered the aluminum electrolytic cell to fall to the discharge The surface of the anode coating material around the mouth, so that the thickness of the anode coating material of the aluminum electrolytic cell is gradually increased;

[0012] The above two problems, on the one hand, make it more difficult to clean the subsequent electrode residue covering material, and on the other hand, weaken the normal heat dissipation ability of the covered anode, and at the same time do not use the normal maintenance of the anode covering material of the aluminum electrolytic cell

[0013] (3) In the process of practice, among the covering materials currently used by various electrolytic aluminum enterprises, the proportion of alumina is relatively high (the mass ratio exceeds 60%, and the process is accompanied by the falling of fluorine-loaded alumina materials), and strips are formed during the sintering process. The formation of a new phase of α-alumina leads to a relatively high hardness of the covering material layer after sintering, which brings great difficulties to the subsequent pole change, covering material cleaning and covering material breaking