Patent · US Expired

Heap leaching with oxygen

US4721526A · kind A · utility

51Cited by
4References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 13, 1986
Grant dateJan 26, 1988
Priority date
Expiry dateAug 13, 2006

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC22B11/08
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A method and system for the percolation leaching of gold and silver ores applies a cyanide leaching liquid to a pile of gold and silver ore. Heap leaching, vat leaching, or the like may specifically be practiced. The cyanide leaching liquid is applied to the pile by spraying, flooding, or via a foam of oxygen gas and cyanide liquid on top of the pile. Gold and silver are recovered from the pregnant liquor. The leach rate is increased and/or the recovery of gold and silver from the ore is increased by supplying to the pile a gas containing oxygen at a significantly higher percentage than in ambient air (e.g. pure oxygen gas). The oxygen gas may be supplied to the leaching liquid, and/or into the pile itself (as with a plurality of perforated pipes adjacent the bottom of the pile).

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.