Study On The Influence Of Turbulence Intensity On The Mineralization Of Fluidized Bed Flotation

In view of the fact that the traditional flotation mineralization environment cannot be adjusted according to the properties of the feed,and the countercurrent mineralization method has low mineralization efficiency,low flotation recovery rate,mechanical agitation,and jet mineralization have the characteristics of high energy consumption and extremely uneven turbulence intensity.By adding turbulent flow control particles a new type of mineralization method can create the turbulence intensity required for different flotation feeds,the shortcomings of the above three mineralization methods can be solved.This study mainly focused on the influence of turbulence intensity on the mineralization of fluidized bed flotation.Different turbulence intensity caused by operating factors and changes in bed structure is one of the most critical factors affecting the mineralization process and mineralization effect of the fluidized bed flotation column.Combined with the hydrodynamic characteristics,the effects of changes in operating factors and bed structure on bubble diameter and gas holdup were studied through single-factor and BBD multi-factor experiments.And then the classical model of mineralization between particles and bubbles was analyzed.Finally,the slime test was used to explore the effect of the classification of full-grain slime and each-grain coal slime under various turbulence conditions and verified with the fluid dynamic analysis and mineralization model.The data of bubble diameter and gas holdup during the test were obtained by conductivity probe method and differential pressure method,respectively.The single factor test clarified the distribution law of bubble diameter and gas holdup in the mineralized bed.When the superficial liquid velocity,superficial gas velocity,static bed height and heavy phase mass ratio are 0.2265m/s,0.0255m/s,0.2885 m,and 50%,respectively,the mineralization environment is optimal.Through multi-factor experiments,the influence of the importance and correlation of each factor on the gas parameters was clarified,and prediction models for bubble diameter and gas holdup were obtained,which provided the good conditions for subsequent experiments.Based on a model analysis of the mineralization process between flotation particles and bubbles,it is found that the major parameters influencing the collision probability and collection probability between particles and bubbles are particle size,bubble diameter,superficial liquid velocities,and height of the static bed.When the superficial liquid velocity is 0.2265m/s and the height of the static bed is 0.2885 m,the probability of collision and collection are both the maximum values.Full-grained slime flotation test and clean coal screening results indicates that the optimal mineralization environment is of great significance to the effect of coal slime separation,and match the theoretical model of mineralization.Changes in the surperficial liquid velocity and the height of the static bed cause the turbulence intensity to change,which affects the flotation effect of different granularity slime.Coarsegrained slime has the highest yield under the optimal mineralization environment,and the fine-grained slime requires a higher turbulent mineralization environment,which showed that the corresponding theoretical model of mineralization needs to be improved.In the fluidized bed flotation column,the turbulence regulation by adjusting the surperficial liquid velocity and the height of the static bed can both create the turbulent mineralization intensity required for different feed properties.The research results have a certain reference significance for the fluidized bed flotation column in various operating factors and the design of packed particles.There are 44 figures,24 tables,and 93 references in the paper.