Abstract: A process for changing spent anodes while recovering the majority of the gaseous compounds evolved by the spent anodes and by the bath crust removed from the electrolytic pots during the cooling phase uses an effluent-collection device for electrolytic pots. A device for collecting gaseous effluents from pots for the production of aluminum by igneous electrolysis allows the recovery of the gaseous compounds evolved by the spent anodes and by the crust which they contain during the replacement and cooling of these anodes and this crust. The device preferably includes a degassing and cooling container located at one of the ends of the hooding device of the pots. The container can be made to communicate with the suction produced by the gas collection device.

Abstract: Process for insolubilizing and consolidating in pellet form the spent linings from electrolysis cells for the production of aluminium comprising grinding said spent linings and mixing them thoroughly with various pulverulent refractory additives before heating, characterized in that after the addition of:a first additive intended to fix the alkali metals during firing, which is chosen from the group of aluminosilicates,and subsequently a second additive intended firstly to combine with the impregnating fluoride compounds during firing to form new stable, insoluble compounds, and secondly through its non-combined excess part to assure the consolidation of the mixture, and is chosen from the group of calcium oxides and salts, preferably limestone cements and mortars,the intimate mixture of ground, spent linings and said first and second pulverulent additives is agglomerated into pellet form before firing at a temperature in the range of from 700.degree. C. to 950.degree. C.