Abstract: In order to improve the economic benefits of Qidashan Concentrator，the flotation process was investigated to solve the problem of high grade of flotation tailings in the reverse flotation process of mixed magnetic concentrate. The effects of flotation machine structure，ore feeding properties，operating conditions and production management on the flotation process were studied. The research results show that the large-scale flotation machine is conducive to reducing costs and improving the level of automation. The working parameters of flotation machine，such as air volume，liquid level and reagent system，ore feeding property parameters，such as feed concentration，feed particle size and daily production management，will all significantly affect the flotation effect. The control direction of each influencing factor in the reverse flo⁃ tation process of mixed magnetic separation concentrate in the future is obtained. It is clearly proposed that automation technologies such as intelligent control of flotation tank liquid level，intelligent perception tech⁃ nology of flotation concentrate grade and intelligent control of flotation reagent addition still need to be strengthened and promoted in practical application.

Key words: mixed magnetic concentrate, reverse flotation, flotation machine, feeding property, operat? ing conditions, reagent system, production management