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US 6,207,443 B1Granted
Method for initiating heap bioleaching of sulfidic ores
AssigneePlacer Dome, Inc.
InventorJames A. King
Life of this patent
Estimating the term…
Abstract
The process of the present invention “jump starts” heap biooxidation of sulfides by incorporating a previously biooxidized material into the heap. The process can be used to recover precious and/or base metals from sulfidic ores and concentrate.
Claims20
A process for recovering a metal from a sulfidic feed material containing the metal as a sulfide, comprising:
- (a) comminuting a feed material to form a comminuted material;
- (b) separating the comminuted material by screening into an oversized fraction and an undersized fraction, the oversized fraction having a mean particle size greater than the undersized fraction;
- wherein the undersized fraction constitutes no more than about 15% by weight of the feed material;
- (c) separating the undersized fraction into a coarse undersized fraction and a fine undersized fraction, the coarse undersized fraction having a mean particle size greater than the fine undersized fraction;
- (d) floating at least a portion of the fine undersized fraction to form a tailing fraction and a concentrate fraction, wherein the fine undersized fraction has a P80 size ranging from about 10 to about 200 microns;
- (e) at least partially biooxidizing at least a portion of the concentrate fraction to form a biooxidized fraction, wherein the biooxidized fraction includes an organism for oxidizing the sulfide sulfur in the feed material;
- (f) combining at least a portion of the biooxidized fraction, which includes the organism, and at least a portion of the oversized fraction of the feed material to form a combined feed material;
- and
- (g) thereafter biooxidizing the combined feed material.
6 more elements
A process for recovering a metal from a feed material containing sulfides, comprising:
- (a) separating the feed material into a coarse fraction and a fine fraction, the coarse fraction having a larger mean particle size than the fine fraction and the fine fraction constituting no more than about 30% by weight of the feed material wherein the P80 size of the feed material ranges from about 5 to about 20 mm and the separation is performed using one or more screens having an aperture size ranging from about 1 to about 3 mm;
- (b) floating at least a portion of the fine fraction to form a tailing fraction and a concentrate fraction, wherein the fine fraction has a P80 size ranging from about 5 to about 200 microns and the concentrate fraction constitutes no more than about 5 wt. % of the feed material;
- (c) at least partially biooxidizing the concentrate fraction in a reactor to form a biooxidized fraction, wherein the biooxidized fraction includes an organism for oxidizing the sulfide sulfur in the concentrate fraction to form a first pregnant leach solution containing at least a portion of the metal in the concentrate fraction;
- (d) separating at least most of the first pregnant leach solution from the biooxidized fraction;
- (e) thereafter combining at least a portion of the biooxidized fraction, which includes the organism, and at least a portion of the coarse fraction to form a combined feed material, wherein at least a portion of the coarse fraction has not been biooxidized in the reactor;
- (f) biooxidizing the combined feed material with a lixiviant to form a second pregnant leach solution containing at least a portion of the metal in the combined feed material;
- and
- (g) recovering the metal from the first and second pregnant leach solutions.
5 more elements
A process for recovering a metal from a feed material containing the metal and sulfides, comprising:
- (a) comminuting the feed material to form a comminuted material having a P80 size ranging from about 5 to about 20 mm;
- (b) passing the comminuted material through a screen having an aperture size ranging from about 1 to about 3 mm to form an oversized fraction and an undersized fraction, the oversized fraction having a mean particle size greater than the undersized fraction, wherein the undersized fraction has a P80 size ranging from about 10 to about 200 microns and the undersized fraction represents no more than about 30% by weight of the comminuted material;
- (c) cycloning the undersized fraction to form a coarse undersized fraction and a fine undersized fraction, the coarse undersized fraction having a mean particle size greater than the fine undersized fraction and the fine undersized fraction representing no more than about 20 wt. % of the undersized fraction;
- (d) floating at least a portion of the fine undersized fraction to form a tailing fraction and a concentrate fraction, wherein the concentrate fraction constitutes no more than about 5 wt % of the feed material;
- (e) at least partially biooxidizing the concentrate fraction in a reactor to form a biooxidized fraction, wherein the biooxidized fraction includes an organism for oxidizing the sulfide sulfur in the concentrate fraction to form a first pregnant leach solution containing at least a portion of the metal in the concentrate fraction;
- (f) separating at least most of the first pregnant leach solution from the biooxidized fraction;
- (g) adding a second organism of a different species than the organism in the biooxidized fraction to at least one of the biooxidized fraction and the oversized fraction, the second organism flourishing at temperatures different from the organism present in the biooxidized fraction;
- (h) thereafter combining at least a portion of the biooxidized fraction, which includes the organism, and at least a portion of the oversized fraction to form a combined feed material, wherein at least a portion of the oversized fraction has not been biooxidized in a reactor;
- (i) biooxidizing the combined feed material to form a second pregnant leach solution containing at least a portion of the metal in the combined feed material;
- and
- (j) recovering the metal from the first and second pregnant leach solutions.
8 more elements
Dependencies are inferred from the claim text.