Study On The Flow Field Characteristics Of The Scatterer Gas Bubbler And The Optimization Of The Distributor

Bubble tower as a simple structure of the multiphase reactor,flexible operation in practical use,and high efficiency,it is widely used in chemical and biological flue gas desulfurization processing etc..In recent years,with the continuous development and progress of computer numerical simulation technology,CFD simulation technology has been popular by more and more scholars.Up to now,CFD technology has gradually become an important method for the study of gas-liquid two-phase flow field in bubble column,and provides a new way for the study of flow field in bubble column.This paper uses Fluent software for the first time in the air inlet pipe transverse component scattering bubble column at high superficial gas velocities(Ug=0.1m/s)simulation,simulation of bubbling tower diameter D is 400 mm,four scattering tube diameter d is 40 mm pipe gas distributor,where the ring diameter of d is scattering 0.5D.For the simulation of bubble column 3D physical model,using a single bubble size model and population balance model(Population Balance Model,PBM)were compared to the overall gas holdup simulation results,found that the single bubble size model in high gas velocity of the whole gas holdup is far greater than the experimental measurement results value,and the PBM model to simulate the whole gas holdup is consistent with the experimental situation.In the previous study of the literature simulation,it is found that the liquid often escapes from the outlet,so this new boundary condition is used for the pressure outlet boundary.In the simulation process,the computation amount of computer numerical simulation is greatly reduced,and a lot of working time is saved.Moreover,the simulation results of liquid velocity radial distribution are also more consistent with the actual operation flow field of bubble column.Then put forward the research for most: Schiller-Naumann,Grace and Tomiyama three kinds of drag coefficient force model of the bubble column overall rate of gas distribution simulation analysis is discussed and the local average gas holdup,found that the Tomiyama model obtained results close to the experimental measurements,the most suitable for the bubble column simulation object.Finally,the diameter of the circle d were 0.375 D,0.5D 0.625 D 0.75 D,through the simulation of scattering tube,the four scattering pipe gas distributor arrangement,observe the influence of inlet pipe scattering under different distances on the overall layout and the local gas holdup,liquid velocity and bubble size,the layout of the inlet pipe scattering drum the performance of bubble column reactor,analyzed and optimized the bubbling tower inlet scattering tube arrangement,when the diameter of the circle where the scattering tube d is 0.5D,in this case the bubble column overall gas holdup and liquid circulation velocity,volume average bubble diameter minimum,in this case the bubbling tower the best comprehensive performance.