| Mineral industry is currently facing challenges associated with resources, economy, environment and other aspects, so increasingly importance has been attached to its grim situation. Several decades of theoretical study and industrial production practice show that flotation column is a very effective separation materials equipment, it has characteristics of simple structure, high efficiency, energy saving and obvious advantages of micro-fine flotation. In the ways of increase mineral separation efficiency and comprehensive utilization of recourses, reduce the cost of sorting, flotation column has good prospects for development.This paper summarized the history and current situation of flotation column research and application, discussed the development trend of flotation column. In the study of role of bubble and particle theory and flotation equation, found that to increase the efficiency of flotation column mainly contents as follows: increase collision probability of particle and bubble, minimize bubble size, increase bubble number, high bubble surface area flux, improve adaptability of granularity, thus increase recovery. On the other hands, coarse flotation should shortened distance, reduce disturbance in the floating and risk of desorption. Fine flotation should increase desorption probability and increase selectivity. Conventional flotation column to increase recovery must increase height, the height increase so the bubble size increased, can not satisfy these two requirements simultaneous. And, coarse off easy but fine not easy shedding, conduce the poor selectivity of flotation column at past, and the small particle size application. Therefore, design and produce a flotation machine to solve the bubble diameter and recovery, and expend the scope of particle size is very necessary.Based on the above conditions and requirements, designed ring-like inflatable flotation machine. This machine was made of separate columns, independent bubble generators of air pressure, ring scraper agencies and tailings lifting tube. Several separate columns arranged as a circular ring, and used pressurized air made bubble. Pulp feed into one column, mine tablets down and air bubble rise, hydrophobic ore became thick ore concentrates after flotation process, and into concentrate separate column made many times generation got finally concentrate. Affinity ore along with the pulp, through the tailings lifting tube entered sweeps elects to separate in the column to carry on sweeps many times and got finally tailings. This experiment made the laboratory ring-like inflatable flotation machine. The single column made of Perspex, used air compressor gas, through frequency changer control scraper rotational speed.This paper researched the flotation efficiency of this machine on the theoretical,analyzed the movement trajectory of particles and the force in tailings upgrade tube, researched the bubble speciality and the charge capability, made the mineral processing test and compared to the mechanical agitation-type flotation machine.1.The height of flotation column was high brought many issues, including inconvenient operation and maintenance, consumed too much energy to feed the mineral, needed more pressure of bubble generation in the bottom and replace the bubble generator inconvenient. The height of this machine was far lower than flotation column in the past, so the problems can be avoided completely.2. The theoretical studies showed that, the bubble size inversely to the height of flotation column, but the recovery proportional to the height, conventional flotation column can not solve this contradiction. This machine reduced the actual height and increased the separate room, so the machine reduced the bubble size and enhanced the recovery.The effect of previous flotation column was not good to deal with the coarse and fine particles, because of coarse off easy but fine not easy shedding. The structure of this machine enhanced the risk of collision of coarse with the bubble, and the fine particles increased selectivity because of washed many times.3. This paper researched the efficiency of flotation machine on the theoretical, the lower height avoid a large number of mergers of bubbles, maintained the quantity of small bubbles and improved the micro-fine ore particle separation efficiency. The higher trapping interval ensure that the higher mineral recovery. Multi-column sorting portfolio approach reduced flotation column height and improved the recovery.4. This paper analyzed the movement traiectory of particles in the machine and the single tube, analyzed the force in tailings upgrade tube and get the formulation.5. In this paper, the bubble diameter was made by bubble generator was measured and calculated. Firstly, observed the bubble speed used camera and calculated bubble diameter. Secondly, used the theoretical formulation of microcellular foam estimated the bubble diameter, the results is inosculated to the results of observed.6. Apparent inflatable rate, activator concentration and inflatable pressure have significant impacts to the bubble size, the connection of them in the single column of thie machine was studied in this paper. The bubble diameter increased with the apparent inflatable rate increased, induced with activator concentration increased, and induced with the inflatable pressure increased, but in more than a certain extent, the effect are no longer significant.7. In this paper, the relationships of apparent inflation rate and inflation rate and bubble surface area flux of ring-like flatable flotation machine was studied. And in the state of clean water, found the best value. And this paper studied and got the relatation of bubble surface area flux and inflation rate.8. Made the test parameters of pyrite used the flotation machine, including apparent inflation rate of bubble generator, the inflatable pressure of tailings ascend tube, grinding fineness, pulp concentration, pulp flow and scraper speed. And this paper analyzed the concentrate and tailings of each tube. The results showed that each tube has enriched concentrate and tailings recovery, accord with the design requirements.9. This paper compared the flotation to mechanical agitation-type flotation machine in flotation pyrite. The results showed that, the effect of this flotation machine is better than the effect of mechanical agitation-type flotation machine. In the low-grade pyrite flotation, the flow of ring-like inflatable flotation machine is one rough election and one choiceness and flow of the mechanical agitation-type flotation machine is three rough election and three choiceness. The concentrate grade of this machine is higher 0.18% and attained 52.06%, the recovery of this machine is higher 0.1% and attained 99.15% and the tailings grade is lower 0.05% attained 0.21%.
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