Production line for electrolytic cell cathode blocks

　　Cathode blocks are divided into semi-graphitic aluminum cathodes, high-graphitic aluminum cathodes, and graphitized cathodes.

　　Aluminum cathodes are generally made from high-quality smokeless coal, coke, graphite, etc. Depending on the location of use, they are further divided into bottom blocks, side blocks, connecting blocks (rammed carbon paste or carbon glue), and cathode bars.
　　1. Bottom blocks. These serve a dual purpose of conducting electricity and forming the inner lining of the electrolytic cell. They are laid at the bottom of the electrolytic cell, with refractory materials built externally and reinforced with a steel shell. They can be divided into ordinary cathode blocks, semi-graphitic cathode blocks, and graphitic cathode blocks.
　　2. Side blocks. Used to build the sides of the aluminum electrolytic cell, forming the main body of the cell's side lining. These can be divided into ordinary side blocks and semi-graphitic side blocks; their production methods are similar to bottom blocks. With the increasing use of silicon nitride bonded silicon carbide blocks in the sidewalls of aluminum electrolytic cells, the amount of side blocks used has decreased.
　　3. Cathode bars. These connect the cathode blocks and cathode busbars within the aluminum electrolytic cell, forming the cathode circuit. They are divided into single-bar assembly (one cathode bar is assembled on one cathode block) and double-bar assembly (two cathode bars are assembled at the end of one cathode block).
　　The raw materials for cathode blocks are mainly smokeless coal, pitch coke, artificial graphite, and coal tar pitch. The raw materials are calcined, crushed, and screened into specific particle sizes. After metering according to the formula, a binder is added and kneaded. Once kneading is complete, the finished cathode paste is obtained. The kneaded paste is then formed, baked, and sometimes graphitized and machined to produce cathode blocks.
　　Cathode block production process:

　　Furnace types used: Electric calcination furnace, baking furnace, graphitization furnace