Methods and systems for leaching a metal-bearing ore using a bio-augmentation process

Patent metadata

Field	Value
Publication number	US-10767242-B2
Application number	US-201916425715-A
Country	US
Kind code	B2
Filing date	May 29, 2019
Priority date	Sep 13, 2012
Publication date	Sep 8, 2020
Grant date	Sep 8, 2020

Abstract

A system and method for recovering a metal value from a metal-bearing ore material are provided. A metal-bearing ore can be mixed with certain substances and to form an agglomerated ore. In an intermediate state, between agglomeration and heap formation, bacteria can be added to the metal-bearing ore material to produce an augmented ore. The augmented ore can then be formed into a heap. Bacteria from the heap may be fortified to assist in bacterial growth.

First claim

What is claimed is:

1. A method comprising:
inoculating a first agglomerated ore comprising a metal-bearing material with bacteria to form a first augmented ore;
leaching the first augmented ore comprising bacteria in a heap leach to yield a metal-bearing solution;
directing at least a portion of the metal-bearing solution to a separate growth pond;
adding a nutrient directly to the metal-bearing solution in the separate growth pond to yield a fortified liquid medium; and
directing at least a portion of the fortified liquid medium from the separate growth pond to a second agglomerated ore.

2. The method according to claim 1 , wherein the nutrient comprises at least one of ammonia, phosphate, potassium, magnesium, carbon dioxide, and oxygen.

3. The method according to claim 1 , wherein the fortified liquid medium is held in the growth pond for at least 12 hours prior to the directing.

4. The method according to claim 1 , further comprising heating the fortified liquid medium.

5. The method according to claim 1 , wherein a selectively pressured bacterial colony is formed from directing at least a portion of the metal-bearing solution to the separate growth pond.

6. The method according to claim 5 , wherein the fortified liquid medium comprises an amplified number of bacteria within the selectively pressured bacteria colony.

7. The method according to claim 1 , wherein the nutrient is mixed with an aqueous solution before being added to the separate growth pond.

8. The method according to claim 1 , wherein the nutrient comprises a gaseous nutrient and is bubbled into the separate growth pond.

9. The method according to claim 1 , further comprising covering the separate growth pond with a tarp to control a temperature of the separate growth pond.

10. A method comprising:
leaching an augmented ore comprising bacteria in a heap leach to yield a metal-bearing solution;
pretreating at least a portion of the metal-bearing solution to form a pre-treated metal-bearing solution; and
directing the pre-treated metal-bearing solution to a bioreactor system wherein a bacterial colony is incubated.

11. The method according to claim 10 , wherein the bioreactor system comprises an agitator configured to mix ingredients in the bioreactor system.

12. The method according to claim 10 , wherein the pretreating comprises at least one of pH adjustment, metal value precipitation, separation by density, and filtration.

13. The method according to claim 10 , further comprising directing the pre-treated metal-bearing solution from the bioreactor system to an effluent holding tank.

14. The method according to claim 10 , wherein the pretreating comprises adding a nutrient to the portion of the metal-bearing solution.

15. The method according to claim 14 , wherein the nutrient comprises at least one of ammonia, phosphate, potassium, magnesium, carbon dioxide, and oxygen.

Assignees

• Freeport Minerals Corp

Inventors

• Robertson Joanna M
• Green Christine Rae
• Bowman Gabriel Elias

Classifications

• C22B3/18 Primary

  with the aid of microorganisms or enzymes, e.g. bacteria or algae · CPC title

• C22B3/02

  Apparatus therefor · CPC title

• Y02P10/20

  Recycling · CPC title

• Y02P10/234

  Cross-Sectional Technologies · mapped topic