Device for compensation of magnetic field induced by a neighboring row of high-power reduction cells connected in series

Abstract

A device for compensating a magnetic field in a linearly arranged series of electrolysis cells consists of a combination of main and supplemental electrical compensating conductors. Main inner and outer compensating conductors are spaced from the respective sides of the cells in a series. An inner supplemental compensating conductor is disposed at the bottom of the cells and along the main inner compensating conductor. First and second outer supplemental compensating conductors are disposed at the bottom of the cells. The first supplemental conductor is positioned at the cathode bars at the outer side of the cell. The second outer supplemental conductor is positioned between the first outer supplemental conductor and small axis of the cell.

1 . A device for compensating a magnetic field induced in a linearly arranged series of electrolysis cells by an adjacent generally parallel line of cells, each said electrolysis cell containing a metal shell extending in a vertical direction between top and bottom portions thereof and between internal and external sides in other direction, a cathode device containing at least a plurality of cathode bars, said cells being oriented transverse to an axis of the series, each said shell containing a layer of liquid aluminum, said compensating device comprising: 
 a main internal electrical compensating conductor spaced laterally from the internal sides of said cells in the series, a main external electrical compensating electrical conductor spaced laterally from the external sides of said cells in the series;    at least one internal supplemental electrical compensating conductor disposed under the bottom portion of the cells in the line and in the vicinity of the cathode bars situated at the internal sides of said cells along said main internal compensating conductor;    at least first and second external supplemental electrical compensating conductors disposed at the bottom portion of the cells in the series along said main external compensating conductor, said first external supplemental conductor positioned in the vicinity of the cathode bars situated at the external sides of said cells, said second external supplemental conductor positioned between said first external supplemental conductor and a short longitudinal axis of said cell.    
   
   
       2 . A device according to  claim 1 , wherein said main internal and external electrical compensation conductors are disposed substantially at a level of the layer of liquid aluminum in the respective cell.  
   
   
       3 . A device according to  claim 1 , wherein said cathode bars form a part of a cathode device, said cathode bars are connected by means of a cathode busbar with anode risers of a respective anode device of a downstream electrolysis cell in the series of electrolysis cells.  
   
   
       4 . A device according to  claim 1 , further comprising a source of direct current associated with said compensation conductors, the direction of the direct current in the main internal electrical compensation conductor coincides with the direction of the current in the line of cells, whereas the direction of current in the main external electrical compensation conductor being opposite to the current direction in the line cells.  
   
   
       5 . A device according to  claim 1 , wherein said supplemental compensation conductors being oriented substantially parallel to the main electrical compensation conductors.  
   
   
       6 . A device according to  claim 1 , wherein each said electrolysis cell further comprises a center of the cathode plane of the cell with at least a longitudinal axis and a vertical axis passing through said center, said first and second external supplemental compensation conductors are positioned between said external side of the shell and a plane passing through said short longitudinal axis.  
   
   
       7 . A device according to  claim 6 , wherein said first and second external supplemental compensation conductors are spaced from said bottom portion of the cell.  
   
   
       8 . A device according to  claim 7 , wherein the direction of current in said first and second external supplemental compensation conductors is opposite to the direction of the current in the series.  
   
   
       9 . A device according to  claim 6 , wherein said at least one internal compensation conductor is positioned between said internal side of the shell and said plane passing through the longitudinal axis.  
   
   
       10 . A device according to  claim 9 , wherein the direction of current in said at least one inner supplemental conductor coincides with the direction of the current in the series.  
   
   
       11 . A device according to  claim 6 , wherein said supplemental internal and external compensation conductors are separated from each other by a substantial gap and are positioned on opposite sides of said plane passing through said longitudinal axis.