Abstract: A copper-tin tailings in Yunnan contains tin of 0.65% and iron of 43.58%， which has high recovery value.In order to realize the comprehensive utilization of the tailings resources， the desulfurization flotation of the tailings and cassiterite flotation of the desulfurization tailings was conducted based on the results of process mineralogy.The results showed that tin and iron are the main elements recovered from the tailings and the contents of impurity sulfur is 1.59%.Tin mainly exists in the form of cassiterite， which is closely associated with iron oxide minerals and basically dissociated from pyrite minerals.The distribution rate of tin with -0.074 mm is 69.48%， and the distribution rate of tin with -0.038 mm is also as high as 24.92%. The content of high fine particles will affect the subsequent flotation recovery of cassiterite.The total sulfur recovery of foam products obtained by pre-desulphurization flotation is 72.13% with the tin recovery rate of 6.88%， and the sulfur content in desulphurization tailings is only 0.51%， which achieves the purpose of pre-desulphurization of copper-tin tailings. A tin concentrate with tin grade of 1.63% and tin recovery rate of 63.96% were obtained by one roughing， two cleaning and two scavenging， which realized the effective recovery of tin resources in the tailings.

Key words: copper-tin tailing, desulphurization, cassiterite, flotation