Operational Problems of a Graphitized Cathodic Block Lining in Contemporary Aluminum Electrolyzers

A carbon lining in the form of cathode blocks with a different graphite content under electrolyzer conditions is subjected to mechanical wear as a result of rapid melt movement, and this is more significant than for amorphous carbon blocks. The problem of operating a graphitized cathode block lining is discussed. After performing an autopsy for cathode units the condition of some aluminum electrolyzer lining sections with blocks having a different degree of graphitization is studied. Reasons are examined and determined for premature electrolyzer breakdown with graphite-containing hearth blocks. Results are provided for temperature measurement of high-power electrolyzer cathode units.