关键词: 氰化尾渣, 蓄热还原, 磁化焙烧, 磁选

Abstract: The total cyanide contents of a gold-selecting roasting cyanide tailings from Liaoning Xindu Gold is 719 mg/kg.The main iron minerals in residue is mainly hematite and the TFe grade is of 35.08%.The iron concentrate could be recycled from the cyanide tailings with the decomposition of cyanide efficiently by synchronous iron extraction of per-oxidation and heat-retaining reduction.The results showed that the total cyanide content in cyanide tailings can be reduced to below the detection limit at 550 ℃,25 min in the cyanide-oxidation stage,and the heating of the tailings was completed.Then,under the condition of reduction temperature of 560 ℃,reduction time of 30 min,CO concentration of 40%,gas flow of 500 mL/min,the heat-retaining reduction tests was carried out.The iron concentrate with a TFe grade of 58.94% and the recovery of 89.93% was obtained by low intensity magnetic separation at magnetic field intensity of 143.28 kA/m after being ground to -0.038 mm accounting for 82.02% by rod mill.This process can not only oxidize the cyanide effectively,but also realize efficient recovery and utilization of iron minerals from cyanide tailing.

Key words: cyanide tailings, heat-retaining reduction, magnetizing roasting, magnetic separation