Reinforcing cavities in green carbon bodies during calcination - using a rigid organic foam body, esp. for anodes prodn. for melt electrolysis mfr. of aluminium

摘要

A filler medium for mechanically stabilising cavities in green carbon bodies, in at least the first phase of the calcining process, esp. in plugholes and ventilation ports in anodes for the prodn. of A1 by melt electrolysis, comprises a rigid organic foam which does not react with carbon, and which stands in contact with the side wall(s) and bottom surface of the cavity to maintain the shape of the cavity. The foam is e.g. of phenolic or polyurethane foam material which opt. contains a passive carbon filler such as coke or anthracite with a particle size up to 10 mm.