| Molybdenum is a rare metal and also a strategic reserve resource. It plays an very important role in national economy and human health, and is being largely applied in industrial field. In recent years, with the increasing of exploiting molybdenum, rich mine resources are reducing and the proportion of poverty, fine, miscellaneous, and difficultly-separated molybdenum ores are constantly increasing, so the separation equipment and technology were put forward to higher requirement. In this background, molybdenum mineral shows a typical micro-fine separation characteristics, and two major needs and two research focus exsit. First, the quality of molybdenum concentrate needs furtherly improved. The second is the exploitation and utilization of difficultly-separated molybdenum ore. Column high efficient separation process of Molybdenite and difficultly-separated molybdenum is proposed in this context.This paper analyzed flotability characteristic of molybdenum separation process first. No matter for concentrate process, rough separation or refractory separation, the flotability characteristics follow the same trend,"easy to float for the beginning, further worse and worse, and finally more and more difficult to float". Taking physical properties as background, this thesis points out to apply cyclonic static micro-bubble flotation column separation method to separation of molybdenum, combining with analysis of "non-equilibrium" separation process, and studies its possibilities of application to high efficient separation of molybdenum ore. In addition, system study analyzed the unique function of micro-bubble separating out and foaming on the separation based on the micro-fine and easily floating molybdenum ore. Systematic studies are also carried out on the separation function of mechanism of cyclonic static micro-bubble flotation column separation cyclone field and pipe flow mineralization environment to difficultly-separated particles.Molybdenite column concentrate separation study is first carried out in this paper. The semi-industrial separation test system of molybdenum ores concentration was built up and series of tests has been carried out. On the basis of confirming the conditions of ore consumption, medicament system and operation parameters, continuous operation test are carried out. The test results reveals that, under conditions of using materials after regringding flotation concentrates and average grade value of 5%, consumption 1.5 t/d, one rough process and two concentrate courses of cyclonic static micro-bubble flotation column separation can get 53.21% molybdenum concentrate grade value and 92.95% concentrate separation recovery rate index. Compared with one rough process and two concentrate and one scavenging courses, one rough process and two concentrate courses is finally determined as final testing process. Compared with nine concentrate and one scavenging courses of flotation machine on spot, under conditions of the same feeding materials, using such process, grade value has improved 6.52% and concentrate separation recovery rate has increased 7.31%. Analysis of the concentration process reveals that main factors affecting concentrate separation recovery rate are mainly fineness of milling ores, degree of dissociation and separation solution liquid. Further and deep study find that unique characteristics of pipe flow flotation devices has advantage in isolating and foaming large amount of micro-bubbles, which is beneficial to fine particles materials separation of molybdenum concentrate. Large amount of micro-bubbles not only can greatly improve mineralizing probability and promote the quicking floating of molybdenite particles with extremely good surfacial hydrophobilty.Flotation column cannot be applied to rough separation and full-flow separation, which is weak link of flotation column equipments. On basis of molybdenum concentration, this paper studied on laboratory test and column full-flow separation industrial tests on Liushashan molybdenum mine. Laboratory test determined milling fineness medicament system and milling fineness tests and so on. After confirming conditions of consumption, and circulation gas volume, full-flow separation industrial system tests are carried out. The results reveal that, in view of characteristics that sulphide ore of Liushashan molybdenum ore is easily separated ores, and that oxide molybdenum ore mainly contains difficultly separated powellite, sulphide ores and oxide ores are respectively separated by column technique. One rough process and two concentrate courses are applied for sulphide ore. Desliming separate-coarse separate-one concentration process are applied for oxide ores. Results shows grade value of sulphide molybdenum concentrates is above 45%, grade value of oxide sulphide molybdenum concentrates is above 10%, grade value of comprehensive molybdenum concentrates is above 42%, and comprehensive recovery rate is above 70%. Conclusion can be drawn from analysis of coarse separation and full-flow separation process that, cyclone dynamics construction promotes separation effect of mineralizd air-masses. Re-separation of mid-size ores circular returning increases chances of mineralized separation of difficultly separated particles, so recovery rate in coarse separation process can be promoted.This paper made a column separation research on Yechangping oxide molybdenum ores. Testing system from laboratory to industrial practices are build up and series of tests on difficultly separated oxide molybdenum ores are carried out on this basis. laboratory fine slime separation test shows that, flotation column has advantage over flotation machines on fine slime separation. Result of Semi-industrial partial flow tests dedicates that, using column one rough process and two concentrate courses to separate difficultly separated oxide molybdenum ores can get 28.55% molybdenum concentration grade value, 59.52% recovery rate, and one rough process and two concentrate courses process is identified as final testing process. Result of column fine slime technical industrial application tests shows that, using column one rough process and two concentrate courses can get average 26.9% concentrates grade value, average 0.080% tailings grade value, average 57.81% recovery rate. Each obtained indexes all close to semi-industrial test. Column fine slime separation process can make the whole producing system molybdenum concentrates index increase 2.33%, tailings grade value reduce 0.01%, average recovery rate improve 5.28%. Analysis of separation process show that, high-intensity turbulent separation environment of cyclonic static micro-bubble flotation column is beneficial to separation of difficultly separated molybdenum ores with poor floating properties and also has obvious effect on improving separation efficiency of difficulty separated molybdenum ores.This paper explores cyclonic static micro-bubble flotation column through a host of experiments and theoretical researches on the basis of analysis of separation process. In this paper cyclonic static micro-bubble flotation column are applied to different high efficient separation processes as molybdenite concentration, molybdenum ores full-flow separation and difficlutly molybdenum ores separation. It also provides a method for highly efficient utilizing national molybdenum resources.
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