METHOD FOR RECOVERY OF METALS FROM METAL-CONTAINING MATERIALS USING MEDIUM TEMPERATURE PRESSURE LEACHING
The present invention relates generally to a process for recovering copper and other metal values from metal-containing materials using controlled, super-fine grinding and medium temperature pressure leaching. Processes embodying aspects of the present invention may be beneficial for recovering a variety of metals such as copper, gold, silver, nickel, cobalt, molybdenum, rhenium, zinc, uranium, and platinum group metals, from metal-bearing materials, and find particular utility in connection with the extraction of copper from copper sulfide ores and concentrates.
1 . A method for recovering a metal value from a metal-bearing material, the method comprising the steps of:
providing a feed stream comprising a metal-bearing material;
grinding said feed stream to form an inlet stream having a uniform ultra-fine particle size distribution;
leaching said inlet stream at a temperature of from about 140° C. to about 180° C. and at a pressure of from about 100 psi to about 750 psi to form a metal-containing solution; and
recovering at least one metal value from said metal-containing solution.
2 . The method according to claim 1 , wherein said step of providing a feed stream comprising a metal-bearing material comprises providing a feed stream comprising a copper sulfide ore or concentrate.
3 . The method according to claim 1 , wherein said step of grinding said feed stream comprises super-fine grinding said feed stream to form an inlet stream having a particle size distribution of P98 less than about 25 microns.
4 . The method according to claim 1 , wherein said step of grinding said feed stream comprises super-fine grinding said feed stream to form an inlet stream having a particle size distribution of P98 of from about 10 to about 23 microns.
6 . The method according to claim 1 , wherein said step of grinding said feed stream comprises super-fine grinding said feed stream to form an inlet stream having a particle size distribution of P98 of from about 13 to about 15 microns.
7 . The method according to claim 1 , wherein said step of leaching said inlet stream comprises leaching said inlet stream at a temperature of from about 160 to about 170° C. and at a pressure of from about 100 psi to about 750 psi.
8 . The method according to claim 1 , wherein said step of leaching said inlet stream comprises leaching said inlet stream in the presence of a surfactant.
9 . The method according to claim 1 , wherein said step of leaching said inlet stream comprises leaching said inlet stream in the presence of calcium lignosulfonate.
10 . A method for recovering metal from a metal-bearing material, the method comprising the steps of:
providing a feed stream comprising a metal-bearing material;
subjecting at least a portion of said feed stream to controlled, super-fine grinding to form an inlet stream, wherein said controlled, super-fine grinding comprises reducing the particle size of said feed stream to a P98 of less than about 25 microns;
leaching at least a portion of said inlet stream in the presence of oxygen at an elevated temperature and pressure to form a metal-bearing solution; and
recovering at least one metal value from said metal-bearing solution.
11 . The method according to claim 10 , wherein said step of leaching said inlet stream comprises leaching said inlet stream at a temperature of from about 140° C. to about 180° C. and at a pressure of from about 100 psi to about 750 psi.
12 . The method according to claim 10 , wherein said step of leaching said inlet stream comprises leaching said inlet stream at a temperature of from about 150° C. to about 175° C. and at a pressure of from about 100 psi to about 750 psi.
13 . The method according to claim 10 , wherein said step of leaching said inlet stream further comprises leaching said inlet stream in the presence of a surfactant.
14 . The method according to claim 10 , wherein said step of leaching said inlet stream further comprises leaching said inlet stream in the presence of a surfactant selected from the group consisting of lignin derivatives, orthophenylene diamine, alkyl sulfonates, and mixtures thereof.
15 . The method according to claim 10 , wherein said step of providing a feed stream comprising a metal-bearing material comprises providing a feed stream comprising a copper sulfide ore or concentrate.
16 . A system for recovering a metal value from a metal-containing material, the system comprising:
a feed stream comprising a metal bearing material;
a means for controlled, super-fine grinding of said feed stream to reduce the particle size of said feed stream to P98 of less than about 25 microns;
a processing device operable to receive at least a portion of said feed stream and operable to leach said portion of said feed stream in an oxidizing environment at an elevated pressure and temperature to yield a metal-bearing solution; and
a means for recovering at least one metal value from said metal-bearing solution.
17 . The system according to claim 16 further comprising a means for conditioning said metal-bearing solution before said step of recovering at least one metal value.
18 . The system according to claim 16 , wherein said elevated pressure is from about 100 psi to about 750 psi and said elevated temperature is from about 140° C. to about 180° C.
19 . The system according to claim 16 , wherein said feed stream has a particle size of P98 from about 10 to about 23 microns.
20 . The system according to claim 16 , wherein said metal-bearing material comprises at least one of copper sulfide ore and copper sulfide concentrate.