Specialized metallurgical processes – compositions for use therei – Processes – Free metal or alloy reductant contains magnesium
Patent
1994-06-23
1995-10-03
Rosenberg, Peter D.
Specialized metallurgical processes, compositions for use therei
Processes
Free metal or alloy reductant contains magnesium
75738, 75739, 423140, C22B 322, C22B 2300
Patent
active
054548560
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to a process for recovering nickel that is in soluble form in a liquor.
In many instances, the liquor from a leaching or beneficiation circuit for oxidised nickel-containing ore contains nickel in dissolved form in relatively low concentrations, typically up to 2% by weight. The preferred known method of recovering valuable species, such as nickel, that is in low concentrations in a liquor is to precipitate the valuable species and to pass the liquor through a thickener/filtration circuit to separate the valuable species from the liquor. However, this is not a satisfactory solution for nickel because the nickel precipitates that can be formed most readily, such as nickel hydroxides and sulphides, are gelatinous and difficult to thicken and filter. In particular, the nickel precipitates tend to blind filters quickly. As a consequence, invariably the dissolved nickel is not received from the liquor.
An object of the present invention is to provide a cost-effective process for recovering nickel in soluble form from a liquor.
According to the present invention there is provided a process for recovering nickel in soluble form from a liquor, the process comprising: form flocs comprising nickel precipitate, inert particulate carrier, and flocculent;
It is preferred that the process further comprises passing the nickel precipitates and flocculent through a filter to recover the nickel as a filter cake.
It is preferred that the precipitation step (a) comprises adjusting the pH of the liquor to precipitate the nickel as an hydroxide.
Alternatively, it is preferred that the precipitation step (a) comprises adding sulphur containing compounds to precipitate the nickel as a sulphide.
It is preferred that the separation step (c) comprises allowing the flocs to settle by gravity and separating the relatively clarified liquor from the flocs.
In an alternative form of the invention it is preferred that the separation step (c) comprises recovering the flocs by a magnetic separator.
It is preferred that the separation step (d) be carried out by agitating the flocs.
The term "inert" as used herein in relation to "particulate carrier" is understood to mean that the particulate carrier is not substantially attacked by the liquor. In other words, the term "inert" means that the particulate carrier exhibits both suitable chemical and physical stability in the liquor.
It is preferred that the inert particulate carrier be selected from the group consisting of sand, alumina, magnetite, hematite, ilmenite and calcite.
It is preferred that the flocculent be a polyelectrolyte flocculent. The term "polyelectrolyte flocculent" as used herein is understood to mean any suitable cationic, non-ionic and anionic flocculent.
The present invention is described further with reference to the accompanying drawings in which:
FIG. 1 is a flow sheet of the main steps in a preferred embodiment of the process of the present invention; and
FIG. 2 is a flow sheet of the main process steps in a pilot plant trial of the process of the present invention.
With reference to FIG. 1, in a preferred embodiment of the process of the invention, a liquor from a leaching or beneficiation circuit for soluble oxidised nickel-containing ore is conditioned in a series of tanks by pH adjustment or addition of a suitable sulfur-containing compound to precipitate the nickel as an hydroxide or sulphide.
The resultant liquor containing a suspension of the nickel precipitate, an inert particulate carrier, and a polyelectrolyte flocculent are mixed together in a suitable form of mixing vessel in amounts selected to form flocs of the nickel precipitate and the inert particulate carrier.
The flocs and a relatively small part of the liquor are then separated from the major part of the liquor by allowing the flocs to settle under gravity of directing the liquor in a stream pat a magnetic separator so that the flocs are recovered on the magnetic separator.
The separated flocs and the relatively small part of the liquor are agitated to break-up the floc
REFERENCES:
patent: 5238663 (1993-08-01), Vikari
Modern Environmental Service Trust
Rosenberg Peter D.
LandOfFree
Recovery of nickel in soluble form from a liquor does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Recovery of nickel in soluble form from a liquor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Recovery of nickel in soluble form from a liquor will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1074921