Back to results
US 4,256,706 AGranted
Leaching agglomerated gold - silver ores
AssigneeThe United States of America as represented by the Secretary of the Interior
InventorsHarold J. Heinen, Gene E. McClelland, Roald E. Lindstrom
Life of this patent
Estimating the term…
Abstract
Percolation leaching of gold or silver ores, tailings or wastes is accomplished by a process comprising initial agglomeration of fines in the feed by means of a binding agent and cyanide solution, followed by aging and, subsequently, leaching to recover gold or silver values.
Claims7
A process for percolation leaching of gold or silver values from a feed material consisting of ores, tailings or wastes comprising:
- (1) admixing the feed with about 0.25 to 0.75 weight percent of a binding agent consisting of lime, portland cement, or mixtures thereof, and about 8 to 16 weight percent of an aqueous cyanide solution,
- (2) mechanically manipulating the admixture to effect agglomeration of fines in the feed,
- (3) aging the admixture at ambient conditions for a time sufficient to provide the resulting agglomerates with green strength sufficient to withstand further wetting without disintegration, and for substantial reaction of the cyanide with gold or silver values in the feed, and
- (4) subjecting the aged admixture to percolation leaching with water or cyanide solution, whereby gold or silver is selectively leached.
1 more element
Dependencies are inferred from the claim text.