Abstract: In this paper, the industrial test on the step-flotation of ire ore containing high carbonate iron in Dong'anshan was studied on the basis of the early lab researches. The flotation concentrate with Fe grade of 64.80% and the Fe recovery 72.89% has been gained in the industrial test, which confirms the feasibility of step-flotation process in industrial application. During the tests, the entire process of rough concentration-gravity separation-magnetic separation-step flotation was investigated. The results indicated that the iron ore containing high ferric carbonate in Dong'anshan that can not be used in the past now was exploited by the step-flotation, obtaining comprehensive iron concentrate with Fe grade 63.02%, and Fe recovery of 63.77%. 

Key words: Dong'anshan high carbonate iron ore, Mixed concentrate of magnetic separation, Step-flotation, Industrial test