METHOD FOR RECOVERING CYANIDE FROM A BARREN SOLUTION

摘要

A process is disclosed for recovering cyanide used to leach gold or silver from ore. In the course of leaching gold or silver from ore, a barren solution is generated. A portion of the barren solution containing sodium cyanide is recycled to the cyanidation proc ess while blowdown from the barren solution is subjected to pre-treatment, UV photodissociati on and pH adjustment. Ultimately, a volatile hydrocyanic acid is formed and is absorbed into a sodium hydroxide solution through the employment of a gas-filled membrane. This forms sodium cyanide that can be recycled and used in the cy anidation process to leach gold or silver from ore.