EP0177295A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Recovery of gold from refractory auriferous iron-containing sulphidic material
Assignee: Viridian Inc Canada
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Filing: 1985-09-27
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Granted: —
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Expires: 2005-09-27
Abstract
Abstract In a process for the recovery of gold from refractory auriferous iron containing sulphidic material which comprises subjecting an aqueous feed slurry of the sulphidic material to a pressure oxidation step (14), and recovering the gold from the oxidized solids, e.g. by cyanidation (22), problems associated with elemental sulphur formation in the oxidation step are alleviated by adding inert mateial, preferably by recycle of oxidized solids, to the feed slurry to provide an initial pulp density in the range 30-60% by weight.
Inventors
- 👤 Donald R. Weir
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 21:56
CPC Classifications
C; C22; C22B; C22B11/00; C22B11/04; C22B11/08
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
117 words
A process for the recovery of gold from refractory auriferous iron containing sulphidic material which comprises subjecting an aqueous slurry of the ground ore to pressure oxidation at a temperature in the range 120° to 250°C and at a total pressure in the range 360 to 6000 kPa in a pressure oxidation step (14), and thereafter recovering the gold from the oxidized solids, characterised in that there is added to the slurry fed to the oxidation step additional solids, which are relatively inert under the oxidizing conditions prevailing in the oxidation step, such additional solids providing a slurry which, at least in the initial stages of oxidation, has a pulp density In the range 30-60% by weight.
Claim 2
Dependent Claim
117 words
A process for the recovery of gold from refractory auriferous iron containing sulphidic material which comprises subjecting an aqueous slurry of the ground ore to pressure oxidation at a temperature in the range 120° to 250°C and at a total pressure in the range 360 to 6000 kPa in a pressure oxidation step (14), and thereafter recovering the gold from the oxidized solids, characterised in that there is added to the slurry fed to the oxidation step additional solids, which are relatively inert under the oxidizing conditions prevailing in the oxidation step, such additional solids providing a slurry which, at least in the initial stages of oxidation, has a pulp density In the range 30-60% by weight.
Claim 3
Dependent Claim
29 words
A process according to claim 1, characterised in that said initial pulp density of the feed slurry in the oxidation step is from 40 to 55% solids by weight.
Claim 4
Dependent Claim
32 words
A process according to claim 1 or 2, characterised in that the weight ratio of said additional solids to fresh feed material in said slurry is in the range 0.5:1 to 10:1.
Claim 5
Dependent Claim
18 words
A process according to claim 3, characterised in that said ratio is in the range 2.5:1 to 4:1.
Claim 6
Dependent Claim
41 words
A process according to any one of claims 1-4, characterised in that said pulp density is achieved by recycling a portion of the oxidized solids recovered from the oxidation step (14) to the feed slurry as said relatively inert additional solids.
Claim 7
Dependent Claim
28 words
A process according to claim 5, characterised in that said oxidized solids are recycled to the feed slurry by recycling oxidized slurry directly from the pressure oxidation step.
Claim 8
Dependent Claim
29 words
A process according to claim 5, characterised in that said recycled oxidized solids are first of all separated from the oxidized slurry in a solids- liquid separation step (18).
Claim 9
Dependent Claim
28 words
A process according to claim 7, characterised in that the oxidized slurry from the pressure oxidation step is washed prior to or during the liquid-solids separation step (18).
Claim 10
Dependent Claim
63 words
A process according to any one of claims 1-8, characterised in that, following the oxidation step (14), the gold is recovered from the oxidized solids, or from that portion of the oxidized solids that is not recycled, as the case may be, by neutralizing those solids in a neutralization step (20) and subsequent cyanidation of those neutralized solids in a cyanidation step (22).
References Cited (Backward Citations)
No citation records indexed.
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