Apparatus for use in electrorefining and electrowinning

Abstract

An apparatus for use in the electroproduction or electrorefining which includes first and second electrodes, at least one bus bar, and at least one power supply wherein a power supply is associated with an electrode and is arranged to regulate a current supply from a bus bar to the electrode.

1 . An apparatus for use in the electroproduction or electrorefining, comprising:
 first and second electrodes;   at least one bus bar; and   at least one power supply;
 wherein a power supply is associated with an electrode and is arranged to regulate a current supply from a bus bar to the electrode. 
   
     
     
         2 . The apparatus as claimed in  claim 1 , further comprising a controller associated with each power supply to maintain the current flow to the electrode at a predetermined value. 
     
     
         3 . An apparatus as claimed in  claim 2 , wherein each controller is adjacent to or part of its associated power supply. 
     
     
         4 . The apparatus as claimed in  claim 1 , in which each power supply includes a current monitoring device and each associated controller controls the operation of the power supply in response to current measurements made by the current measuring device. 
     
     
         5 . The apparatus as claimed in  claim 1 , wherein at least one of the power supplies is operated as a current source. 
     
     
         6 . The apparatus as claimed in  claim 1 , wherein at least one of the power supplies is switched mode power converter, wherein at least one of the power supplies includes one or more power semiconductor switches, and the duty cycle of operation of the power supply is greater than 20 kHz. 
     
     
         7 . The apparatus as claimed in  claim 1 , wherein at least one of the power supplies provides auxiliary power in addition to that provided by the bus bars. 
     
     
         8 . The apparatus as claimed in  claim 1 , wherein the electrode includes a plurality of protrusions arranged to rest on the bus bars. 
     
     
         9 . The apparatus as claimed in  claim 8 , wherein the at least one power supply is disposed between one or more of the plurality of protrusions and the bus bars, or is incorporated into the protrusions, or the hanger bar, or is incorporated into or on an electrode. 
     
     
         10 . The apparatus as claimed in  claim 1 , wherein the at least one power supply is disposed between a hanger bar and the electrode. 
     
     
         11 . The apparatus as claimed in  claim 1 , wherein one of the electrodes comprises a first side and a second side and wherein the first side and the second side are electrically isolated from one another, and wherein current flow in the first side of the electrode is controlled independently of current flow in the second side of the electrode. 
     
     
         12 . The apparatus as claimed in  claim 1 , wherein a plurality of power supplies are mutually associated with the same electrode and cooperate with each other to share control and predetermined current information relating to the associated electrode. 
     
     
         13 . The apparatus as claimed  claim 1 , further including at least one step down transformer, to reduce a supply voltage to an intermediate voltage for input to the power supplies. 
     
     
         14 . The apparatus as claimed in  claim 1 , where at least some connectors between the at least one power supply, hanger bars, the electrodes and the at least one bus bar comprise contacts which press against a cooperating conductive surface. 
     
     
         15 . The apparatus of  claim 1 , comprising actuators for controlling a separation between the first electrode and the second electrode as a function of at least one of:
 evolution of current-voltage characteristic between the first electrode and the second electrode;   electrode condition; and   time.   
     
     
         16 . The apparatus of  claim 1 , comprising:
 a plurality of electrodes; and   current sensors associated with at least some of the electrodes, and output or data-processing circuits for outputting or processing the current measurements.