Abstract: In an aged copper and cobalt mine tailings abroad, the grade of Cu and Co are 0.97% and 0.080%, respectively. The copper mainly exists in the form of copper oxide, accounting for 88.66% of the to⁃ tal copper. For the ores, -0.074 mm particles accounted for 77.31% and -0.038 mm particles accounted for 53.01%. And Cu and Co obviously enriched in the fraction of +0.15 mm. However, the distribution rate of Cu and Co was not high in the fraction due to its low yield. In order to determine the appropriate recovery process of copper and cobalt from the tailings, preconcentration of copper and cobalt by flotation was car⁃ ried out, and then the roughing concentrate was leached in sulfuric acid at room temperature. The flotation results showed that the roughing concentrate is with Cu grade of 5.37%, Co grade of 0.325%, Cu recovery rate of 63.99% and Co recovery rate of 48.88%. The acid consumption in acid leaching is 7.53 t/t, and Cu and Co leaching rates of the rough concentrate were 80.16% and 69.87%, which indicating the better pre⁃ concentration effect. The acid comsumption in acid leaching after preconcentration decreased compared with direct acid leaching, which had remarkable economic and environmental benefits.

Key words: tailings, copper, cobalt, flotation, leaching