Anode servicing assembly for an aluminium electrolysis plant, and methods for operating the same

Abstract

An anode servicing assembly ( 30, 35 ) for an aluminium electrolysis plant, said aluminium electrolysis plant comprising at least one line (L 1 , L 2 ) of electrolysis cells (C 1 -Cn, C′ 1 -C′n) connected in series, each cell having a plurality of anode assemblies ( 5 ) connected to an anode beam, said anode servicing assembly comprising: an elongated body ( 31 ), running means adapted to allow movement of said elongated body along a running direction, substantially parallel to main axis of said line (L 1 , L 2 ), an anode servicing machine ( 32 ) mounted on said elongated body, said anode servicing machine comprising at least two operating devices ( 45, 55, 65, 75, 85, 95 ), each adapted to fulfil at least one specific function different from cell lifting and anode beam raising, at least two support assemblies ( 40, 50, 60, 62, 70, 72, 80, 81, 82, 83, 90, 91, 92, 93 ), each adapted to support a respective operating device with respect to said elongated body, said operating devices ( 45, 55, 65, 75, 85, 95 ) being movable independently the one with respect to the other, along at least one of a longitudinal axis (L 31 ) of said elongated body ( 31 ) and a vertical axis (ZZ).

1 - 14 . (canceled) 
     
     
         15 . An anode servicing assembly for an aluminium electrolysis plant having at least one line of electrolysis cells connected in series, each electrolysis cell being connected to a cathodic busbar and each electrolysis cell having a plurality of anode assemblies connected to an anode beam, the anode servicing assembly comprising:
 an elongated body formed as a beam;   a running mechanism adapted to allow movement of the elongated body along a running direction substantially parallel to a main axis of the at least one line; and   an anode servicing machine mounted on the elongated body, the anode servicing machine including:
 at least two operating devices, each operating device adapted to fulfil at least one specific anode servicing function, the anode servicing function being different from cell lifting and anode beam raising, 
 at least two support assemblies, each support assembly adapted to support a respective operating device with respect to the elongated body, the at least two operating devices being movable independently the one with respect to the other, along at least one of a longitudinal axis of the elongated body and a vertical axis. 
   
     
     
         16 . The anode servicing assembly of  claim 15 , wherein at least one support assembly of the at least two support assemblies comprises at least one carrier movable with respect to the elongated body along the longitudinal axis of the elongated body, the respective operating device being fixed with respect to the at least one carrier, at least in translation. 
     
     
         17 . The anode servicing assembly of claim  14 , wherein at least one support assembly of the at least two support assemblies comprises:
 at least one carrier movable with respect to the elongated body along the longitudinal axis of the elongated body, and   at least one drive member provided with a driving mechanism adapted to move a corresponding operating device with respect to the at least one carrier along the vertical axis.   
     
     
         18 . The anode servicing assembly of  claim 17 , wherein at least one support assembly of the at least two support assemblies comprises two carriers, and two drive members, the driving mechanism being adapted to move one single operating device with respect to the two carriers along the vertical axis. 
     
     
         19 . The anode servicing assembly of  claim 18 , wherein the elongated body comprises at least two parallel rails, at least one rail being provided with at least one track for translation motion of at least one carrier of the two carriers. 
     
     
         20 . The anode servicing assembly of claim  14 , wherein at least one specific anode servicing function is chosen between: lifting a new anode, vacuum cleaning anode cover material surrounding and/or covering an anode, sawing solid crust material surrounding an anode, lifting of the spent anode, placing the new anode at specific height, adding anode cover material on and around an anode, recording images representative of the position and the shape of an anode, moving a hood panel giving access to an anode, and moving back the hood panels after completing the anode change. 
     
     
         21 . The anode servicing assembly of claim  14 , wherein each operating device of the at least two operating devices has a lifting power that is less than 10 metric tons. 
     
     
         22 . The anode servicing assembly of claim  14 , further comprising at least two lifting operating devices adapted for lifting a respective anode assembly. 
     
     
         23 . The anode servicing assembly of  claim 22 , further comprising a multi-use operating device having a head adapted to cooperate with:
 first tools detachably fixed on a distinct operating device, and/or   second tools detachably fixed on the multi-use operating device.   
     
     
         24 . An aluminium electrolysis plant, comprising:
 at least one line of electrolysis cells of substantially rectangular shape, the at least one line having at least one anode servicing assembly that includes;
 a body, 
 a running mechanism adapted to allow movement of the body along the running direction, and 
 an anode servicing machine mounted on the body and adapted to fulfil at least one specific anode servicing function that includes at least one of a heavy lifting function, and/or a main function that is distinct from the at least one specific anode servicing functions, 
   a first connector for electrically connecting the electrolysis cells in series;   a second connector for connecting a cathodic busbar of a cell to an anode beam of a downstream electrolysis cell;   at least one heavy lifting assembly including:
 a first elongated body formed as a beam, 
 a first running mechanism adapted to allow movement of the first elongated body along a running direction, substantially parallel to main axis of the at least one line, 
 a heavy lifting machine mounted on the first elongated body and adapted to fulfil at least one heavy lifting function which includes lifting of pre-lined pot shells, pot shells with failed linings, and superstructures; 
   at least one pot tending assembly including:
 a second elongated body formed as a beam, 
 a second running mechanism adapted to allow movement of the second elongated body along a running direction, substantially parallel to main axis of the at least one line, 
 a pot tending machine mounted on the second elongated body and adapted to fulfil at least one main function which includes raising of anode beams and tapping, 
   wherein at least one of the specific anode servicing functions is distinct from heavy lifting functions and main functions of the main type.   
     
     
         25 . The aluminium electrolysis plant of  claim 24 , further comprising at least one common running path adapted to cooperate with the first running mechanism and the second running mechanism and/or the pot tending assembly. 
     
     
         26 . The aluminium electrolysis plant of  claim 24 , further comprising two common running paths provided on either side of the electrolysis cells, with reference to a transversal axis of the at least one line. 
     
     
         27 . A method of operating an anode servicing assembly of an aluminium electrolysis plant, the method comprising:
 lifting a replacement anode assembly with a first lifting operating device of the anode servicing assembly, the replacement anode assembly to replace a spent anode assembly;   moving the anode servicing assembly that is carrying the replacement anode assembly, adjacent to the spent anode assembly;   lifting the spent anode assembly with a second lifting operating device of the anode servicing assembly;   placing the replacement anode assembly at an original location of the spent anode assembly;   analysing a shape of the spent anode assembly to determine a height position of the replacement anode;   vacuum cleaning material surrounding the spent anode assembly, stocking at least part of the material and pouring at least part of a stocked material around the replacement anode assembly.   
     
     
         28 . The method of  claim 27 , further comprising:
 positioning a heavy lifting assembly or a pot tending assembly of the anode servicing assembly above one given electrolysis cell or between two neighbouring electrolysis cells of the plant; and   positioning a first anode servicing assembly above a first electrolysis cell, located on a first side of the given electrolysis cell or the two neighbouring electrolysis cells, with respect to a main axis;   positioning a second anode servicing assembly above a second electrolysis cell, located on a second side of the given electrolysis cell or the neighbouring electrolysis cells, with respect to the main axis;   conducting at least one specific anode servicing function on the first electrolysis cell and/or on the second electrolysis cell.