(1)conducting electricity;(2)As a container for liquid aluminum and electrolyte.
Requirements for cathode carbon block:
1. Good electrical conductivity,
The cathode carbon block is the electrode, the lower the conductivity is, the lower the resistance is, the lower the pressure drop of the cathode is, which is beneficial to energy saving.
2. Low thermal conductivity
This reduces the heat loss at the bottom of the tank.
3. High thermal shock resistance
Thermal shock resistance of cathode carbon block refers to its resistance to rapid cooling, rapid heating or thermal stability.
4. Good contact with: cathode steel rod
Objective to reduce the cathode pressure drop.
5: high wear resistance
Liquid aluminum electrolyte and slag in the flowing state will produce different degrees of abrasion on the cathode carbon block.The high wear resistance of cathode carbon block is beneficial to improve the life of electrolyzer.
6. Low porosity
To reduce direct penetration of aluminum, electrolyte, or sodium, the cathode carbon block is required to have a low porosity to improve tank life.
7. High corrosion resistance:
In addition to the corrosion of aluminum and electrolyte under high temperature, especially sodium resistance.
Two basic requirements for side cathode carbon block
1: low conductivity
In order to prevent side leakage.
2: high thermal conductivity
To increase the lateral heat dissipation, and conducive to the formation of lateral leg.
3: antioxidant: high elasticity
In addition, the demand side cathode carbon block high thermal shock resistance, high abrasion resistance, low degree of hole, high corrosion resistance, high temperature resistant.
