Method for homogenizing current distribution in aluminum liquid in aluminum electrolytic cell

Abstract

The invention discloses a cathode structure of an aluminum electrolytic cell, in particular to a method for homogenizing current distribution in aluminum liquid in the aluminum electrolytic cell. At least one cathode steel bar is bound or cast at the lower part of a cathode carbon block, and the cathode steel bar is segmented into a plurality of parts in different positions by partition joints in the length direction; cathode steel bars among the partition joints are completely connected with the cathode carbon block through electric conductors, and the rest of the cathode steel bars on the partition joints are completely insulated with the cathode carbon block through insulators; partition joint insulating material is filled in each partition joint, so that the cathode steel bars on and below the partition joints are insulated; and one end of the cathode steel bar penetrates out of the side part of the electrolytic cell. According to the method disclosed by the invention, the current distribution in the aluminum liquid in the aluminum electrolytic cell is homogenized, horizontal current in the aluminum liquid is greatly reduced, the stability of the electrolytic cell is improved, the electrolytic cell can operate with high efficiency at low polar distance, the aluminum energy consumption per ton can be effectively reduced, the energy-saving effect is significant and the service life of a cathode is simultaneously prolonged.

Description

technical field [0001] The invention relates to an aluminum electrolytic cell for producing primary aluminum by the Hall-Erou electrolysis method, in particular to a method for homogenizing the current distribution in the aluminum liquid of the aluminum electrolytic cell. Background technique [0002] Metal aluminum is produced industrially by molten salt electrolysis, that is, electrolytically dissolving alumina in an electrolyte with molten cryolite as the main component. At present, the main method used is the Hall-Heroult electrolysis method. [0003] The direct equipment for the production of electrolytic aluminum is an electrolytic cell. The electrolytic cell is mainly composed of two parts, one part is the anode, usually made of carbon materials, and the other part is the cathode, which is made of carbon blocks and lining materials. [0004] The aluminum electrolytic cell is connected in series in the whole electrolytic series. The current enters the electrolytic cel...

AI Technical Summary

Problems solved by technology

In the electrolytic cell of this structure, there is a very big disadvantage in the cathode conductive structure: because the cathode steel rod and the cathode carbon block are placed horizontally in the same direction, a very large horizontal current is generated in the aluminum liquid, which is in line with the vertical magnetic field in the aluminum liquid The combined action produces electromagnetic force, which drives liquid aluminum to flow and fluctuate in the electrolytic cell. If the horizontal current in the electrolytic cell is too large and unevenly distributed, it will cause excessive fluctuations in the interface between the molten aluminum and the electrolyte, causing the electrolytic Slots create severe instabilities in production, reducing current efficiency

In addition, the horizontal current distribution in the aluminum liquid is unevenly distributed along the length direction of the cathode carbon block, so that the current density at the end of the cathode carbon block is the largest, thereby significantly accelerating the corrosion of the cathode carbon block here and reducing the life of the electrolytic cell

[0006] In order to improve the stability of the electrolytic cell, the usual practice is to strictly control the distribution of the vertical magnetic field in the molten aluminum in the design of the electrolytic cell, which not only increases the difficulty of the design of the cathode busbar, but also leads to complex cathode configuration, large amount of busbar, and increased investment

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