Process for recovery of copper from copper-bearing material using medium temperature pressure leaching, direct electrowinning and solvent/solution extraction

Abstract

The present invention relates generally to a process for recovering copper from a metal-bearing ore, concentrate, or other copper-bearing material using pressure leaching and direct electrowinning. More particularly, the present invention relates to a substantially acid-autogenous process for recovering copper from chalcopyrite-containing ore using pressure leaching and direct electrowinning in combination with a leaching, solvent/solution extraction and electrowinning operation.

1 . A method of recovering copper from a metal-bearing material, comprising the steps of: 
 (a) providing a feed stream comprising a metal-bearing material;    (b) subjecting at least a portion of said feed stream to controlled, super-fine grinding;    (c) leaching at least a portion of said inlet stream in an oxidizing environment at an elevated temperature and pressure to yield a product slurry comprising a metal-bearing solution and a residue;    (d) conditioning said product slurry without the use of solvent/solution extraction techniques to yield a metal-bearing solution suitable for electrowinning;    (e) electrowinning copper from said metal-bearing solution to yield cathode copper and a metal-bearing lean electrolyte stream;    (f) recycling a portion of said lean electrolyte stream to said leaching stage; and    (g) processing a portion of said lean electrolyte stream using solvent/solution extraction techniques.    
     
     
         2 . The method of  claim 1 , wherein said step of providing a feed stream comprising a metal-bearing material comprises providing a feed stream comprising a copper-bearing sulfide ore, concentrate, or precipitate.  
     
     
         3 . The method of  claim 1 , wherein said step of providing a feed stream comprising a metal-bearing material comprises providing a feed stream comprising at least one of chalcopyrite, chalcocite, bornite, covellite, digenite, and enargite, or mixtures or combinations thereof.  
     
     
         4 . The method of  claim 3 , wherein said step of providing a feed stream comprising a metal-bearing material comprises providing a feed stream comprising chalcopyrite.  
     
     
         5 . The method of  claim 1 , wherein said step of providing a feed stream comprising a metal-bearing material comprises providing a feed stream comprising a metal-bearing material and a solution stream comprising copper and acid.  
     
     
         6 . The method of  claim 1 , wherein said step of subjecting at least a portion of said feed stream to controlled, super-fine grinding comprises reducing the particle size of said feed stream such that substantially all of the particles in said feed stream react substantially completely during pressure leaching.  
     
     
         7 . The method of  claim 6 , wherein said step of subjecting at least a portion of said feed stream to controlled, super-fine grinding comprises reducing the particle size of said feed stream to a P98 of less than about 25 microns.  
     
     
         8 . The method of  claim 6 , wherein said step of subjecting at least a portion of said feed stream to controlled, super-fine grinding comprises reducing the particle size of said feed stream to a P98 of from about 10 to about 23 microns.  
     
     
         9 . The method of  claim 6 , wherein said step of subjecting at least a portion of said feed stream to controlled, super-fine grinding comprises reducing the particle size of said feed stream to a P98 of from about 13 to about 15 microns.  
     
     
         10 . The method of  claim 1 , wherein said leaching step comprises leaching at least a portion of said feed stream in a pressure leaching vessel.  
     
     
         11 . The method of  claim 1 , wherein said leaching step comprises leaching at least a portion of said feed stream in a pressure leaching vessel at a temperature of from about 140° C. to about 180° C. and at a total operating pressure of from about 50 psi to about 750 psi.  
     
     
         12 . The method of  claim 11 , wherein said leaching step further comprises injecting oxygen into the pressure leaching vessel to maintain an oxygen partial pressure in the pressure leaching vessel of from about 50 psi to about 250 psi.  
     
     
         13 . The method of  claim 1 , wherein said step of pressure leaching said feed stream comprises pressure leaching said feed stream in the presence of a surfactant selected from the group consisting of lignin derivatives, orthophenylene diamine, alkyl sulfonates, and mixtures thereof.  
     
     
         14 . The method of  claim 1 , wherein said step of pressure leaching said feed stream comprises pressure leaching said feed stream in the presence of calcium lignosulfonate.  
     
     
         15 . The method of  claim 1 , wherein said conditioning step comprises subjecting at least a portion of said product slurry to solid-liquid separation, wherein at least a portion of said metal-bearing solution is separated from said residue.  
     
     
         16 . The method of  claim 15 , wherein said conditioning step further comprises blending at least a portion of said metal-bearing solution with at least a portion of one or more metal-bearing streams to achieve a desired copper concentration in said metal-bearing solution.  
     
     
         17 . The method of  claim 15 , wherein said conditioning step further comprises blending at least a portion of said metal-bearing solution with at least a portion of one or more metal-bearing streams to achieve a copper concentration of from about 15 grams/liter to about 80 grams/liter in said metal-bearing solution.  
     
     
         18 . The method of  claim 15 , wherein a portion of said metal-bearing solution is recycled to step (c).  
     
     
         19 . The method of  claim 1 , wherein said conditioning step comprises subjecting at least a portion of said product slurry to filtration, wherein at least a portion of said metal-bearing solution is separated from said residue.  
     
     
         20 . The method of  claim 1 , wherein said conditioning step comprises separating at least a portion of said reside from said metal-bearing solution in said product slurry, and further comprises using at least a portion of said reside as a seeding agent in step (c).  
     
     
         21 . The method of  claim 1 , further comprising the step of (h) using a portion of said lean electrolyte stream in a leaching operation.  
     
     
         22 . The method of  claim 21 , wherein said step of using a portion of said lean electrolyte stream in a leaching operation comprises using a portion of said lean electrolyte stream in at least one of a heap leaching operation, a stockpile leaching operation, a vat leaching operation, a tank leaching operation, a pressure leaching operation, or an in-situ leaching operation.  
     
     
         23 . A method of recovering copper from a metal-bearing material, comprising the steps of: 
 (a) providing a feed stream comprising a metal-bearing material;    (b) subjecting at least a portion of said feed stream to controlled, super-fine grinding,    (c) leaching at least a portion of said inlet stream in an oxidizing environment at an elevated temperature and pressure to yield a product slurry comprising a metal-bearing solution and a residue;    (d) recycling at least a portion of said product slurry to said leaching step;    (e) conditioning said product slurry without the use of solvent/solution extraction techniques to yield a metal-bearing solution suitable for electrowinning;    (f) electrowinning copper from said metal-bearing solution to yield cathode copper and a metal-bearing lean electrolyte stream; and    (g) processing a portion of said lean electrolyte stream using solvent/solution extraction techniques.    
     
     
         24 . The method of  claim 23 , wherein said step of providing a feed stream comprising a metal-bearing material comprises providing a feed stream comprising a copper-bearing sulfide ore, concentrate, or precipitate.  
     
     
         25 . The method of  claim 23 , wherein said step of providing a feed stream comprising a metal-bearing material comprises providing a feed stream comprising at least one of chalcopyrite, chalcocite, bornite, covellite, digenite, and enargite, or mixtures or combinations thereof.  
     
     
         26 . The method of  claim 23 , wherein said step of providing a feed stream comprising a metal-bearing material comprises providing a feed stream comprising a metal-bearing material and a solution stream comprising copper and acid.  
     
     
         27 . The method of  claim 23 , wherein said step of subjecting at least a portion of said feed stream to controlled, super-fine grinding comprises reducing the particle size of said feed stream such that substantially all of the particles in said feed stream react substantially completely during pressure leaching.  
     
     
         28 . The method of  claim 27 , wherein said step of subjecting at least a portion of said feed stream to controlled, super-fine grinding comprises reducing the particle size of said feed stream to a P98 of less than about 25 microns.  
     
     
         29 . The method of  claim 27 , wherein said step of subjecting at least a portion of said feed stream to controlled, super-fine grinding comprises reducing the particle size of said feed stream to a P98 of from about 10 to about 23 microns.  
     
     
         30 . The method of  claim 27 , wherein said step of subjecting at least a portion of said feed stream to controlled, super-fine grinding comprises reducing the particle size of said feed stream to a P98 of from about 13 to about 15 microns.  
     
     
         31 . The method of  claim 23 , wherein said leaching step comprises leaching at least a portion of said feed stream in a pressure leaching vessel at a temperature of from about 140° C. to about 180° C. and at a total operating pressure of from about 50 psi to about 750 psi.  
     
     
         32 . The method of  claim 23 , wherein said leaching step further comprises injecting oxygen into the pressure leaching vessel to maintain an oxygen partial pressure in the pressure leaching vessel of from about 50 psi to about 250 psi.  
     
     
         33 . The method of  claim 23 , wherein said conditioning step comprises subjecting at least a portion of said product slurry to solid-liquid separation, wherein at least a portion of said metal-bearing solution is separated from said residue.  
     
     
         34 . The method of  claim 35 , wherein said conditioning step further comprises blending at least a portion of said metal-bearing solution with at least a portion of one or more metal-bearing streams to achieve a copper concentration of from about 15 grams/liter to about 80 grams/liter in said metal-bearing solution.  
     
     
         35 . The method of  claim 23 , further comprising separating said product slurry into a liquor component and a solid component prior to step (d), and wherein said recycling step (d) comprises recycling said solid component to leaching step (c).  
     
     
         36 . The method of  claim 23 , wherein said conditioning step comprises separating at least a portion of said reside from said metal-bearing solution in said product slurry, and further comprises using at least a portion of said residue as a seeding agent in leaching step (c).  
     
     
         37 . A method of recovering copper from a metal-bearing material, comprising the steps of: 
 (a) providing a feed stream comprising a metal-bearing material;    (b) subjecting at least a portion of said feed stream to controlled, super-fine grinding,    (c) leaching at least a portion of said inlet stream in an oxidizing environment at an elevated temperature and pressure to yield a product slurry comprising a metal-bearing solution and a residue;    (d) conditioning said product slurry without the use of solvent/solution extraction techniques to yield a metal-bearing solution suitable for electrowinning,    (e) recycling at least a portion of said product slurry to said leaching step;    (f) electrowinning copper from said metal-bearing solution to yield cathode copper and a metal-bearing lean electrolyte stream;    (g) recycling a portion of said lean electrolyte stream to said leaching stage; and    (h) processing a portion of said lean electrolyte stream using solvent/solution extraction techniques.    
     
     
         38 . The method of  claim 39 , wherein said step of providing a feed stream comprising a metal-bearing material comprises providing a feed stream comprising a copper-bearing sulfide ore, concentrate, or precipitate.  
     
     
         39 . The method of  claim 39 , wherein said step of providing a feed stream comprising a metal-bearing material comprises providing a feed stream comprising a metal-bearing material and a solution stream comprising copper and acid.  
     
     
         40 . The method of  claim 39 , wherein said step of subjecting at least a portion of said feed stream to controlled, super-fine grinding comprises reducing the particle size of said feed stream such that substantially all of the particles in said feed stream react substantially completely during pressure leaching.  
     
     
         41 . The method of  claim 39 , wherein said step of subjecting at least a portion of said feed stream to controlled, super-fine grinding comprises reducing the particle size of said feed stream to a P98 of less than about 25 microns.  
     
     
         42 . The method of  claim 39 , wherein said leaching step comprises leaching at least a portion of said feed stream in a pressure leaching vessel at a temperature of from about 140° C. to about 180° C. and at a total operating pressure of from about 50 psi to about 750 psi.  
     
     
         43 . The method of  claim 39 , wherein said conditioning step comprises subjecting at least a portion of said product slurry to solid-liquid separation, wherein at least a portion of said metal-bearing solution is separated from said residue.  
     
     
         44 . The method of  claim 45 , wherein said conditioning step further comprises blending at least a portion of said metal-bearing solution with at least a portion of one or more metal-bearing streams to achieve a copper concentration of from about 15 grams/liter to about 80 grams/liter in said metal-bearing solution.  
     
     
         45 . The method of  claim 39 , wherein said conditioning step comprises separating at least a portion of said reside from said metal-bearing solution in said product slurry, and further comprises using at least a portion of said reside as a seeding agent in leaching step (c).  
     
     
         46 . A method of recovering copper from a metal-bearing material, comprising the steps of: 
 (a) providing a feed stream comprising a metal-bearing material;    (b) subjecting at least a portion of said feed stream to controlled, super-fine grinding;    (c) leaching at least a portion of said inlet stream in an oxidizing environment at an elevated temperature and pressure to yield a product slurry comprising a metal-bearing solution and a residue;    (d) conditioning said product slurry without the use of solvent/solution extraction techniques to yield a metal-bearing solution suitable for electrowinning;    (e) electrowinning copper from said metal-bearing solution to yield cathode copper and a metal-bearing lean electrolyte stream; and    (f) processing a portion of said lean electrolyte stream using solvent/solution extraction techniques.    
     
     
         47 . The method of  claim 48 , wherein said step of providing a feed stream comprising a metal-bearing material comprises providing a feed stream comprising a copper-bearing sulfide ore, concentrate, or precipitate.  
     
     
         48 . The method of  claim 48 , wherein said step of providing a feed stream comprising a metal-bearing material comprises providing a feed stream comprising a metal-bearing material and a solution stream comprising copper and acid.  
     
     
         49 . The method of  claim 48 , wherein said leaching step comprises leaching at least a portion of said feed stream in a pressure leaching vessel at a temperature of from about 140° C. to about 180° C. and at a total operating pressure of from about 50 psi to about 750 psi.  
     
     
         50 . The method of  claim 48 , wherein said conditioning step comprises subjecting at least a portion of said product slurry to solid-liquid separation, wherein at least a portion of said metal-bearing solution is separated from said residue.  
     
     
         51 . The method of  claim 48 , wherein said conditioning step further comprises blending at least a portion of said metal-bearing solution with at least a portion of one or more metal-bearing streams to achieve a copper concentration of from about 15 grams/liter to about 80 grams/liter in said metal-bearing solution.  
     
     
         52 . The method of  claim 48 , further comprising the step of recycling a portion of said lean electrolyte stream from said electrowinning step (e) or a portion of said product slurry from said leaching step (c) to said leaching step (c).