Abstract: There is 198.20 g/t silver in a high lead silver zinc leaching residue from smelting plant of Northwest.Silver mainly exists in form of silver sulfide and metallic silver,followed by silver oxide and silicate and other forms,silver are mainly distributed in 53~20 μm fraction,the distribution rate is as high as 71.48%.For high efficient development and utilization of the secondary sources,the technological conditions for the flotation of silver were studied.Results show that at grinding fineness of -0.037 mm 90%,using Na₂S as Zn2+ remover and silver oxide activator,CuSO₄ as activator of silver-bearing sphalerite,ammonium aerofloat as collector,MIBC as frother,via one roughing-two cleaing-one scavenging,silver concentrate with silver content and recovery of 1 316.80 g/t and 72.02% respectively can be obtained.

Key words: High lead silver zinc leaching residue, Flotation, Zn2+ removal agent, Activator