Method and apparatus for electrowinning copper using an atmospheric leach with ferrous/ferric anode reaction electrowinning

Abstract

The present invention relates, generally, to a method and apparatus for recovering metal values from a metal-bearing materials, and more specifically, a process for recovering copper and other metals through leaching, electrowinning using the ferrous/ferric anode reaction, and the synergistic addition of ferrous iron to the leach step.

1 . A method of recovering a metal value from an ore comprising:
 leaching an ore to yield a metal bearing slurry comprising a metal value and ferrous iron;   separating said metal bearing slurry into a metal bearing solution comprising said metal value and a first portion of said ferrous iron and a metal bearing solid comprising a second portion of said ferrous iron;   recycling said second portion of said ferrous iron to be combined with said ore; and   electrowinning said metal bearing solution by oxidizing said first portion of ferrous iron to ferric iron at an anode of an electrowinning cell and reducing said metal value at a cathode of said electrowinning cell.   
     
     
         2 . The method according to  claim 1 , further comprising recycling said ferric iron to be combined with said ore. 
     
     
         3 . The method according to  claim 1 , further comprising reducing at least a portion of said ferric iron to said ferrous iron during said leaching said ore. 
     
     
         4 . The method according to  claim 1 , further comprising grinding said ore before said leaching said ore. 
     
     
         5 . The method according to  claim 1 , further comprising plating said metal value onto a cathode substrate. 
     
     
         6 . The method according to  claim 1 , wherein said metal value is copper. 
     
     
         7 . The method according to  claim 1 , further comprising a precious metal recovery step. 
     
     
         8 . A method comprising:
 leaching an ore to yield a metal bearing slurry comprising ferrous iron, wherein said leaching occurs at atmospheric pressure;   separating said metal bearing slurry into a metal bearing solution comprising a first portion of said ferrous iron and a metal bearing solid comprising a second portion of said ferrous iron;   recycling at least a portion of said second portion of said ferrous iron to said leaching step;   extracting a metal value and said ferrous iron from said metal bearing solution to yield a rich electrolyte; and   electrowinning said rich electrolyte by oxidizing said first portion of ferrous iron to ferric iron at an anode of an electrowinning cell and reducing said metal value at a cathode of said electrowinning cell.   
     
     
         9 . The method according to  claim 8 , further comprising conditioning said metal bearing solution before said oxidizing said metal bearing solution. 
     
     
         10 . The method according to  claim 8 , further comprising recycling said ferric iron to said leaching step. 
     
     
         11 . The method according to  claim 10 , further comprising reducing said ferric iron to said ferrous iron during said leaching step. 
     
     
         12 . The method according to  claim 8 , further comprising grinding said ore before said leaching said ore.