Abstract:With the gradual depletion of easily processed ore resources，refractory low-grade micro-fine minerals have become the focus of current resource development and utilization. Due to the characteristics of large specific surface area，light weight and high surface energy of fine minerals，it is easy to produce problems such as large reagent consumption，non-selective agglomeration of mineral particles and high pulp viscosity in flotation. One of the core ideas for fine particle flotation is to increase the apparent particle size of minerals or reduce the bubble size，in which micro-nano bubble technology，as a key means to reduce the bubble size，can promote the flotation of target minerals by strengthening the interaction between bubbles and particles. In this paper，taking rutile， cassiterite and mica as typical cases，the separation difficulties of micro-fine minerals are described，and the flotation strengthening effect of micro-nano bubbles on micro-fine ores is systematically analyzed. At the same time，the generation mode and characteristics of micro-nano bubbles are introduced，which provides a reference for the further study of their efficient preparation and stability mechanism. Finally，the mechanism of micro-nano bubbles in the flotation of typical micro-fine minerals is illustrated from three dimensions of strengthening the role of collectors， improving the collision probability and adhesion，and promoting bubble mineralization，in order to provide a reference for the research and engineering application of this technology.