Inflatable Performance Test And Numerical Simulation Of Cavitation Bubble Generator

A bubble generator is the key part of flotation column, it will complete the inflation to the pulp and make the air bubble mineralization, its performance directly influents that the separation effect is good or bad, so the study of structural design of bubble generator is very important. Bubble generator is important equipment for the air supply of flotation column. Making use of the characteristics that cavitation bubbles is in favor of flotation, we designed the porous plate bubble generator and the improved jet bubble generator by ourselves, and set up the flotation column test system according to the need of experimental projects. Through the adjustment of differernt flotation test parameters and different parameters of the cavitation bubble generator itself, we conducted a study on the water experiment of flotation column.Porous plate bubble generator and the improved jet bubble generator that based on the theory of cavitation are selected as the researching object. In clear water conditions, we conducted the water aeration experiment with external inflation. We studied gas bearing state of flotation column by the differential pressure method, discussed the two different types of bubble generator for inflatable flotation column volume situations in different operating parameters, structural parameters and physical parameters, and explored the law of factors influencing the gas holdup in flotation column. Through analysis of test results we can find that in the use of porous plate bubble generator, performance of porous plate bubble generator(11hole) is better, and when the circulating pressure is0.09MPa, aeration rate is0.4m3/h, per cubic meter of water we add the200g foaming agent (DL-2-Octanol), flotation column gas rate reached the highest content(10.11%). In the use of improved jet bubble generator, the performance of the improved jet bubble generator (throat length,66.4mm) is better, and when the circulating pressure is0.12MPa, aeration rate is0.3m3/h, per cubic meter of water we add the200g foaming agent (DL-2-Octanol), flotation column gas rate reached the highest content (10.46%).The fluid flow in cavitation bubble generator is very complicate and the measurement of flow field parameters is rather difficult. In order to understand the fluid flow status inside the cavitation bubble generator. In this thesis, we modeled after reasonable assumptions and applicate the multiphase flow model of the commercial fluid solving-software FLUENT. Through the two kinds of cavitation bubble generator for air and water flow mix progress numerical simulation, we analyzed and summarized the working mechanism of the mixed air and water within the bubble generator, and knew the the parameter distribution of the flow field inside the cavitation bubble generator. Through the numerical simulation, we can accurately predict the pressure and flow field distribution within the computational domain, and have a relatively clear understanding of the concentration of the gas, liquid and the turbulivity field distribution.We expounded the mechanism of cavitation bubble foam generator, and briefly discussed the application the theory of cavitation in the bubble generator, and finally put forward the current problems and possible research direction to solve the problem.