Leaching Method

Patent metadata

Field	Value
Publication number	US-2025092488-A1
Application number	US-202218292089-A
Country	US
Kind code	A1
Filing date	Jul 28, 2022
Priority date	Jul 28, 2021
Publication date	Mar 20, 2025
Grant date	—

Abstract

A method of leaching a gold/copper-containing sulfidic mined material that includes two leach stages, with a gold leach stage leaching gold from the material with a gold leach liquor and a copper leach stage leaching copper from the material with a copper leach liquor.

First claim

1 . A method of leaching a gold/copper-containing sulfidic mined material that includes two leach stages, with a gold leach stage leaching gold from the material with a gold leach liquor and a copper leach stage leaching copper from the material with a copper leach liquor.

2 . The method defined in claim 1 wherein leach conditions are selected so that there is substantially no copper leached in the gold leach stage.

3 . The method defined in claim 1 wherein leach conditions are selected so that there is substantially no gold leached in the copper leach stage.

4 . (canceled)

5 . The method defined in claim 1 wherein the gold leach stage is a heap leach stage.

6 . The method defined in claim 1 wherein the copper leach stage is a heap leach stage.

7 . The method defined in claim 1 includes separate recovery stages for recovering gold and copper from respective gold-containing and copper-containing solutions from the leach stages and producing recovered gold and copper streams and spent gold-containing and copper-containing solutions.

8 . (canceled)

9 . (canceled)

10 . The method defined in claim 1 wherein the gold/copper-containing material is a mined ore or a mined waste material and the method includes:
(a) the gold leach stage comprising leaching gold from the mined ore or the mined waste material with the gold leach liquor and producing a gold-containing solution and a gold-depleted ore; and
(b) the copper leach stage comprising leaching copper from the gold-depleted ore with the copper leach liquor and producing a copper-containing solution.

11 . The method defined in claim 1 wherein the gold/copper-containing material is a mined ore or a mined waste material and the method includes:
(a) the copper leach stage comprising leaching copper from the material with the copper leach liquor and producing a copper-containing solution and a copper-depleted material; and
(b) the gold leach stage comprising leaching gold from the copper-depleted material with the gold leach liquor and producing a gold-containing solution.

12 . The method defined in claim 10 includes forming a heap of the material and carrying out the gold leach stage and the copper leach stage successively on the material in the heap.

13 . The method defined in claim 11 includes forming a heap of the material and carrying out the copper leach stage and the gold leach stage successively on the material in the heap.

14 . The method defined in claim 12 includes a heap washing stage between successive leach stages.

15 . (canceled)

16 . The method defined in claim 1 includes carrying out the gold leach stage out under acidic conditions.

17 . The method defined in claim 1 wherein the gold leach stage is a thiourea-based leach in which thiourea (CS(NH 2 ) 2) acts as a complexing/extracting agent for gold that facilitates leaching gold from the ore material.

18 . The method defined in claim 1 includes controlling the ferric concentration in the gold leach liquor so as not to leach copper in the gold leach stage.

19 . (canceled)

20 . The method defined in claim 1 includes controlling the Eh of the gold leach liquor to be in a range of 350-550 mV in the gold leach stage.

21 . The method defined in claim 1 includes carrying out the copper leach stage under acidic conditions.

22 . (canceled)

23 . The method defined in claim 1 wherein the copper leach stage includes conducting the leach stage with the leach liquor in the presence of silver as a copper leach catalyst and an activation agent that activates silver such that the silver enhances copper leaching.

24 . The method defined in claim 1 includes controlling the heap temperature to be less than 75° C. in the copper leach stage.

25 . (canceled)

26 . The method defined in claim 1 includes controlling the oxidation potential of the copper leach liquor during an active leaching phase of the copper leach stage to be less than 700 mV.

27 . (canceled)

28 . (canceled)

29 . (canceled)

30 . A heap leaching operation for leaching a gold/copper-containing sulfidic mined material that comprises:
(a) a heap of a mined material and/or agglomerated fragments of the mined material; (b) a leach liquor supply unit for supplying to the heap a gold leach liquor for carrying out a gold leach stage on the material in the heap; (c) a leach liquor supply unit for supplying to the heap a copper leach liquor for carrying out a copper leach stage on the material in the heap; (d) a gold recovery unit for recovering gold from a gold-containing solution discharged from the heap during the course of the gold leach stage and producing a recovered gold stream and a spent gold-containing solution; and (e) a copper recovery unit for recovering copper from a copper-containing solution discharged from the heap during the course of the copper leach stage and producing a recovered copper stream and a spent copper-containing solution.

Assignees

• Tech Resources Pty Ltd

Inventors

• Tapera Tendekayi
• Hackl Ralph Peter
• Malysiak Nicola

Classifications

• C22B15/0086

  by physical methods · CPC title

• C22B15/0006

  by dry processes · CPC title

• C22B11/04 Primary

  by wet processes (extraction of metal compounds by leaching in organic solutions C22B3/16; treatment or purification of solutions by liquid-liquid extraction C22B3/26) · CPC title

• C22B3/22

  by physical processes, e.g. by filtration, by magnetic means {, or by thermal decomposition} (treatment or purification of solutions by liquid-liquid extraction C22B3/26) · CPC title

• C22B3/205

  using adducts or inclusion complexes · CPC title