Cathode elements for a hall-héroult cell for aluminium production and a cell of this type having such elements installed

Abstract

A cathode element (1′) for an electrolysis cell of Hall-Heroult type for producing aluminium, comprises a body (4) of calcinated carbonaceous material connected with the upper side of a metallic collector plate (2). A space between the said carbonaceous body and the collector plate being filled with an electric conductive material preferably comprising conductive particles. The collector plate (2) further can comprise at least one horizontal outlet (5, 5′) on at least one side and/or at least one vertical metallic current outlet (7) connected to the lower side of the collector plate (2). In one embodiment the collector plate is divided in two sections (20; 20). The invention also relates to a cell of Hall-Heroult type utilizing such cathode elements (1).

1 . A cathode element for an electrolysis cell of Hall-Héroult type for producing aluminium, comprising a carbonaceous body ( 4 ) of calcinated carbonaceous material connected with the upper side of a metallic collector plate ( 2 ), wherein a space between the said carbonaceous body ( 4 ) and the collector plate ( 2 ) being filled with an electric conductive material, preferably comprising conductive particles,
 wherein 
 the collector plate ( 2 ) further comprises at least one horizontal current outlet ( 5 ,  5 ′) on at least one side and/or at least one vertical metallic current outlet ( 7 ) connected to the collector plate ( 2 ). 
 
     
     
         2 . The cathode element according to  claim 1 ,
 wherein   the carbonaceous body ( 4 ) is rodded to the collector plate ( 2 ) in a manner where the outer end part of the carbonaceous body ( 4 ) is electrically insulated from the collector plate ( 2 ), at a distance up to 450 mm from the end thereof and inwards.   
     
     
         3 . The cathode element according to  claim 1 ,
 wherein   the carbonaceous body ( 4 ) is rodded to the collector plate ( 2 ) in a manner where the outer end part of the carbonaceous body ( 4 ) is electrically insulated from the collector plate ( 2 ) at different lengths on both ends of the plate (asymmetric).   
     
     
         4 . The cathode element according to  claim 1 ,
 wherein   at least one thermocouple (TC) is inserted into a metallic component inside of or below the collector plate ( 2 ).   
     
     
         5 . The cathode element according to  claim 1 ,
 wherein   it comprises at least one horizontal current outlet ( 5 ;  50 ) integrated with the collector plate ( 2 ;  20 ).   
     
     
         6 . The cathode element according to  claim 5 ,
 wherein   the at least one horizontal current outlet ( 5 ;  50 ) is integrated in a slot (S) in the collector plate ( 2 ;  20 ).   
     
     
         7 . The cathode element according to  claim 5 ,
 wherein   the horizontal current outlet ( 5 ;  50 ) comprises one current conductor part ( 5 ;  50 ) that is integrated to the collector plate ( 2 ;  20 ) by a press-fit (knock) fixation in a recess of the collector plate ( 2 ;  20 ) that is complementary with the corresponding part of the conductor ( 5 ,  50 ).   
     
     
         8 . The cathode element according to  claim 5 ,
 wherein   the part of the current conductor ( 5 ;  50 ) integrated to the collector plate ( 2 ;  20 ) has a delta shaped part ( 51 ).   
     
     
         9 . The cathode element according to  claim 5 ,
 wherein   it comprises at least one horizontal current outlet ( 5 ,  5 ′) on each end being integrated with the collector plate ( 2 ).   
     
     
         10 . The cathode element according to  claim 9 ,
 wherein   the cross section of or the insertion length of the horizontal current outlet at one end is different of that of the other end (asymmetric).   
     
     
         11 . The cathode element according to  claim 5 ,
 wherein   the current outlet ( 5 ;  50 ) comprises a copper conductor preferably covered by a protective sheet ( 6 ;  60 ).   
     
     
         12 . The cathode element according to  claim 1 ,
 wherein   it comprises at least one vertical current outlet ( 7 ) arranged at the opposite side of the collector ( 2 ) plate than the said carbonaceous body ( 4 ).   
     
     
         13 . The cathode element according to  claim 12 ,
 wherein   the vertical outlet ( 7 ) comprises of a socket ( 10 ) integrated with the collector plate ( 2 ) wherein a rod-shaped current conductor ( 11 ) is attached to the socket ( 10 ).   
     
     
         14 . The cathode element according to  claim 13 ,
 wherein   the socket ( 10 ) is of a metallic material and further welded to the collector plate ( 2 ).   
     
     
         15 . The cathode element according to  claim 13 ,
 wherein   the socket ( 10 ) has an internal recess ( 17 ′) where an upper part ( 17 ) of the current conductor ( 11 ) has a shape complementary with said recess ( 17 ′) for fixation of said current conductor ( 11 ) to the socket ( 10 ).   
     
     
         16 . The cathode element according to  claim 13 ,
 wherein   the fixation is a press-fit (knock) fixation.   
     
     
         17 . The cathode element according to  claim 13 ,
 wherein   the socket ( 10 ) has internal threads  13  at its outermost end for receiving a sleeve ( 12 ′) with complementary external threads ( 16 ′), wherein the sleeve surrounds the current conductor ( 11 ) and where the end of the sleeve abuts an annular flange or ring ( 14 ′) at the current rod ( 11 ) for forcing the rod ( 11 ) into the socket ( 10 ) when tightened.   
     
     
         18 . The cathode element according to  claim 13 ,
 wherein   there is a threaded bolt ( 17 ) at the top of the socket communicating with a threaded bore ( 17 ′).   
     
     
         19 . The cathode element according to  claim 12 ,
 wherein   the current conductor ( 11 ) is made out of copper or an alloy thereof.   
     
     
         20 . The cathode element according to  claim 1 ,
 wherein   at least one metallic collector element ( 3 ) is arranged at the upper side of a metallic collector plate ( 2 ), where said collector element ( 3 ) is embedded in a corresponding recess ( 9 ) in the bottom part of said carbonaceous body ( 4 ), the recess being wider than the collector element and being filled with an electric conductive material comprising conductive particles.   
     
     
         21 . The cathode element according to  claim 20 ,
 wherein   there is one or more collector elements ( 3 ), preferably 3 to 7 being separated at a distance of typically 50 mm to 150 mm.   
     
     
         22 . The cathode element according to  claim 20 ,
 wherein   the at least one collector element(s) ( 3 ) is of same length or shorter length than the carbonaceous body ( 4 ).   
     
     
         23 . An electrolysis cell of Hall-Héroult type comprising several cathode elements as defined in c 1 aim  1 ,
 wherein 
 a cell is built with several cathode elements and in a configuration of only the same elements. 
 
     
     
         24 . An electrolysis cell of Hall-Héroult type comprising several cathode elements as defined in c 1 aim  1 ,
 wherein 
 a cell is built with several cathode elements and in a configuration of different elements.