| China’s demand for tungsten increases year by year, as a result, over-exploitation of proved tungsten resource has arisen, the tungsten resource situation is severe. In recent years, the white tungsten resource with high impurity content, low taste, has been exploited, meanwhile, tailings, tungsten scrap and other secondary tungsten resource were recycled. The traditional tungsten smelting equipments exist energy consumption in grinding and leaching process, low leaching rate, long time-consuming insufficient To shorten the tungsten ore leaching time and improve leaching, it is necessary to research equipments for meeting the short and efficient process tungsten smelting and energy-efficient low-grade mixed tungsten ore leaching.The mechanical activation technology is an effective way to tungsten ore strengthen leaching, in this paper, use CFD tools, the performance of the reactor and the flow field characteristics and its influencing factors simulation analysis were researched, which based on mechanical activation of the tungsten ore strengthen soda boiling reactor prototype. The research provided the technical foundation for the structure of the device optimization and amplification.Firstly, the flow field analysis of reactor kettle under the mechanically activated strengthen device was researched, and explored the role of the mechanical activation by using Fluent software, determined the main factors which have a greater impact on the flow field, draft tube, tank height to diameter ratio, impeller mounting height. Then by changing the baffle, draft tube, paddle from the bottom height parameter values reactor kettle flow field simulation test, the law of the flow field parameters, namely the creation of the bezel to enhance the axial effect, when the when the installation height H value is set to10mm weakened just below the baffle the Loopback vortex; draft tube height value is taken as36mm, the inhibition induced by the tapered region of the bottom of the kettle to expand, increasing the mechanical strengthening means feed inlet flow rate conducive to strengthening the leaching; the shroud inclination of90, effectively reduce the speed deadband, the upward velocity along the inner wall of the backflow phenomenon is suppressed, conducive to the strengthening of the process; create effective power evaluation standards, when the stirring blade Effective power down5mm strengthen the best results.In this paper, the factors which affect the reactor fluid mixing process were analyzed, influence relationship between stirring speed, paddle from the base height, feeding place, other parameters and the mixing time was gained. When stirring speed increased from150r/min to240r/min, reduced mixing time12.5s, the power per unit volume increased linearly with reduced mixing time; speed remains unchanged conditions, the position of the paddle down on the basis of the original25mm process, the mixing time is shortened up to6.2s, and the efficiency of mixing not change significantly, the power per unit volume of1.38times, the final analysis to determine121mm was optimized JH paddle mounting height; feeding near the bottom area gained shorter mixing time.On the basis of the simulation analysis, the scale-up research of tungsten ore alkali cooking equipment was carried out. To save energy, the combination of enhanced device amplification program was put forward, which based on the structure and size of the mechanical activation device remained the same, the flow field simulation results about enhanced device combination of two different spatial layout were given,and compared with analysis, then researched the flow field supraposition and strengthening effect Finally, found that the first option was suitable for relatively large height-to-diameter ratio mixed system, while the second program was suitable for relatively small paddle-to-diameter ratio system. |
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