Alumina reduction system

Claim 2

An alumina reduction cell according to claim 1 wherein said hood and feeding means are disposed between the anode and an adjacent sidewall of the cell.

Claim 3

An alumina reduction cell according to claim 1 including feeding means between the anode and an adjacent sidewall at spaced locations lengthwise of the cell, said hood means being pivotably supported adjacent said sidewall on the same side of the cell.

Claim 4

An alumina reduction cell according to claim 1 including an anode having a plurality of continuous anode segments, and individual hood and feeding means for each of said anode segments.

Claim 5

An alumina reduction cell according to claim 1 wherein said plunger means are so arranged that no point on the anode working surface is farther removed horizontally from the nearest of said feed locations than three-fourths the overall anode width across the cell between said sidewalls.

Claim 6

In an alumina reduction cell having an anode, a bath of molten electrolyte containing dissolved alumina, and a blanket of alumina and supporting crust of solidified electrolyte overlying the bath, the improvement which comprises: hood means associated with said crust and blanket, and defining therewith a gas collection enclosure to receive anode reaction gases of the cell; and means for feeding alumina into the bath from inside the gas collection enclosure at spaced locations which are separated sufficiently to preserve integrity of the crust between adjacent locations and outwardly of said hood means as said feeding proceeds, including means for introducing alumina into said hood means adjacent said feeding means in each of said spaced locations.

Claim 7

The improvement of claim 7 in which said feeding means are provided at spaced feed sites which are so disposed that no point on the anode working surface is farther removed horizontally from the nearest feed site than three-fourths the overall anode width across the cell.

Claim 8

In an alumina reduction cell having an anode, a bath of molten electrolyte containing dissolved alumina, and a blanket of alumina and supporting crust of solidified electrolyte overlying the bath, the improvement which comprises: an anode having a plurality of continuous anode segments including permanent casing means for each segment; hood means associated with said crust and blanket, and defining therewith a gas collection enclosure to receive anode reaction gases of the cell; plunger means operable inwardly of said hood means to provide openings through the crust for feeding alumina into the bath and for releasing anode reaction gases into said hood means, said plunger means being so arranged that no point on the anode working surface is farther removed horizontally from the nearest of said plunger means than three-fourths the overall anode width across the cell; said casing means peripherally enclosing the upper side surfaces of the anode segments and their lower surfaces being enclosed within said blanket of alumina for protection against air burning; and said crust and blanket providing a substantially gas-tight cover over the bath whereby said hood means are effective for collecting concentrated anode reaction gases as said feeding proceeds.