关键词: 氰化尾渣, 直接还原焙烧, 熔分, 添加剂, 毒性浸出

Abstract: The cyanide residue from a gold smelting enterprise in Liaoning province contains the iron of 35.93% and the lead of 3.88%， which has certain comprehensive recycling value. An experimental study was carried out on the recovery of iron and lead for the residue by reduction roasting and fusion method. The influence of roasting temperature， roasting time， reducing agent dosage and additive dosage on the iron metallization rate and lead volatilization rate were investigated. The results showed that the metallization rate of iron and volatilization rate of lead reached 99.85% and 95.92% respectively with the roasting temperature of 1 250 ℃， roasting time of 60 min， coke powder dosage of 20% and CaO dosage of 25%. X-ray diffraction and scanning electron microscope analysis results showed that the additive calcium oxide can promote the reduction of iron， volatilization of lead and aggregation of metal iron particles in the roasting process， and has a certain effect of desulfurization. Iron ingots with the iron grade of 90.02%， sulfur contents of 0.016% and iron recovery rate of 88.92% were obtained by melting the roasting slag at 1 600 ℃ for 1 h. The toxicity leaching indexes of the roasting slag were far lower than the National standard. The purpose of harmless and resource utilization of cyanide residue was realized.

Key words: cyanide residue, direct reduction roasting, smelting separation, additive reagent, toxicity leaching