Abstract: An aluminum reduction cell having an outer steel shell, thermal and electrical insulation, and an inner lining comprising at least a floor and sidewalls, the improvement which comprises a gap sealant at least in the region of the transition between the floor and sidewalls, the gap sealant comprises a pourable material characterized by a melting point of greater than 1000.degree. C., a density of greater than 2.7 g/cm.sup.3 and a high degree of resistance to molten electrolyte and molten aluminum.

Abstract: A reduction pot for the production of aluminum by fused salt electrolysis comprises an outer steel shell, thermal insulation and an inner lining essentially of carbon with iron cathode bars embedded in it. The floor insulation comprises at least in part of a mechanically compacted layer of a granular material of ground insulation layers and having essentially a particle size that varies between 0.01 and 8 mm. The sidewalls of the reduction pot contain, up to at most 70% of the height (h) of the cathode bar elements, mechanically compacted granular material from ground insulation layers. Above that the thermally and electrically insulated steel shell is lined with sidewall bricks, and the gap between the sidewall bricks and the floor elements is closed off with the usual ramming mass.

Abstract: A reduction pot for the fused salt electrolytic production of aluminum comprises an outer steel shell, a thermally insulating layer, and an inner lining made essentially of carbon with iron cathode bars embedded in it. At least the lower 75% of the floor insulation is a mechanically compacted layer of a granulate material essentially of particle size ranging up to 8 mm. This granulate contains the fully ground but otherwise untreated insulation layers, without carbon residues which are sorted out mechanically before grinding, from replaced electrolytic cells. The remaining 25% of the floor insulation is a layer of firebrick, ground firebrick and/or smelter alumina. The sidewalls of the steel shell are insulated solely by firebrick.