RECOVERY OF CYANIDE FROM GOLD AND SILVER MILL TAILINGS

摘要

Process for recovering cyanide values from a mill tailings stream remaining after gold and silver have been leached from an ore, by treating the tailings stream containing both ore insolubles and remaining cyanide leachant, without a preliminary filtration, to acidification with an acid to a pH of at least 4, stripping the cyanide values therefrom with a stripping gas in a stripping column such as a baffle plate column wherein the average residence time of the column is sufficiently low that the pH of the stream does not rise above about 4 and the ore insolubles do not plug the column, introducing the stripping gas and stripped cyanide values into an absorbing column containing an alkaline liquor to absorb the cyanide values, recovering the absorbed cyanide values, and removing a stripped tailings stream reduced in cyanide values.