Apparatus for treating waste gases in aluminum cells

Claim 1

IN AN ELECTROLYIC CELL FOR THE PRODUCTION OF ALUMINUM, IN COMBINATION, A CONTAINER ADAPTED TO CONTAIN A LAYER OF MOLTEN ELECTROLYTE AND A CRUST OF FROZEN ELECTROLYTE WHICH IS LOCATED ABOVE AND DEFINES A SPACE WITH THE MOLTEN ELECTROLYTE LAYER; A PLURALITY OF ADJACENT PREBAKED CARBON ANODES EXTENDING THROUGH THE CRUST OF FROZEN ELECTROLYTE AND DIPPING INTO THE MOLTEN ELECTROLYTE LAYER WHEREBY WASTE GASES ARE GIVEN OFF AT SAID ANODES AND ACCUMULATE IN THE SPACE BETWEEN THE MOLTEN ELECTROLYTE LAYER AND THE CRUST OF FROZEN ELECTROLYTE WHEN THE CELL IS IN OPERATION; AND AN ARRANGEMENT FOR REMOVING WASTE GASES FROM SAID CONTAINER, SAID ARRANGEMENT COMPRISING AT LEAST ONE SUBSTANTIALLY RECTANGULAR HOLLOW GAS COLLECTING MEMBER EXTENDING THROUGH THE CRUST OF FROZEN ELECTROLYTE BETWEEN A PAIR OF SAID ANODES SPACED THEREFROM AND HAVING AN OPEN LOWER END COMMUNICATING WITH THE SPACE BETWEEN THE MOLTEN ELECTROLYTE LAYER AND THE CRUST OF FROZEN ELECTROLYTE SO THAT WASTE GASES MY STREAM INTO THE INTERIOR OF SAID MEMBER, SAID MEMBER HAVING A SUBSTANTIALLY DOME SHAPED BOTTOM WALL, A PAIR OF END WALLS EXTENDING UPWARDLY FROM SAID BOTTOM WALL, AND A PAIR OF SIDE WALLS EXTENDING IN PART UPWARDLY AND IN PART DOWNWARDLY FROM SAID BOTTOM WALL SO AS TO DEFINE WITH THE BOTTOM WALL A CHAMBER COMMUNICATING WITH THE SPACE BETWEEN THE MOLTEN ELECTROLYTE LAYER AND THE CRUST OF FROZEN ELECTROLYTE, SAID SIDE WALLS, SAID END WALLS AND SAID BOTTOM WALLS DEFINING BETWEEN THEMSELVES AT LEAST ONE COMPARTMENT LOCATED ABOVE SAID BOTTOM WALL, A PACKING OF HEAT INSULATING MATERIAL IN SAID COMPARTMENT, AND CONDUIT MEANS EXTENDING THROUGH SAID PACKING OF HEAT INSULATING MATERIAL AND COMMUNICATING WITH THE CHAMBER OF SAID COLLECTING MEMBER FOR WITHDRAWING WASTE GASES TEREFROM; AND A PACKING OF HEAT INSULATING MATERIAL ABOVE THE CRUST AND FILLING THE SPACE BETWEEN SAID MEMBER AND THE ANODES ADJACENT THERETO.