Research On Deformation And Particle Removal Of Dust-containing Bubbles In Static Liquid During Rising Process

Bubbling contact washing is an important method for the separation and purification of gas-solid wet washing.Dust-containing bubbles are the unit dust collectors of bubbling contact washing.In order to explore the morphological changes of dust-laden bubbles rising in a static liquid and the effect of the interaction between bubbles on the particle removal rate,with the help of a self-designed bubble rise experimental device and the volume of fluid(VOF)-discrete phase(DPM)coupling model in the computational fluid dynamics software Fluent,experiments and simulations have been carried out on the rising process of dusty bubbles in a static liquid,and investigated the morphological changes of dusty single bubbles of different sizes and different combinations of dusty double bubbles in static liquids.And the law of influence on particle removal rate.The main conclusions are as follows:On the single bubble rising and dust-containing single bubble particle removal experimental devices,the morphological changes of dust-containing and dust-free bubbles during the rising process of static liquid and the removal rate of different particle size particles were experimentally studied.The results show that the rising trajectory of a single bubble in a static liquid is not an absolute straight line,but a certain swing.The swing degree decreases with the increase of bubble size.The smaller the bubble size,the more irregular the shape changes.The addition of fine particles has almost no effect on the morphological change of the bubble rising process,and the removal rate of particles in 8mm bubbles is greater than that of 10mm bubbles.By comparing the experimental results and simulation results of the rising process of a 10mm dust-containing single bubble,the shape of the simulated dust-containing bubble is consistent with the experiment and the trend of grading washing efficiency is consistent,which proves the reliability of the selected model.The three-dimensional VOF-DPM coupling model was used to simulate the deformation of different sizes of dust-bearing single bubbles as they rise in a static liquid,for a given bubble size range,deformation occurs during the bubble rising process.The smaller the bubble size,the more diverse the shape changes during the rising process,as the bubble size increases,the deformation tends to be regular,the bubble deformation promotes the removal of particles.The removal rate of particles with different sizes in different sizes of dust-containing single bubbles is significantly different,and there is a suitable bubble size range for efficient removal.The ascending process of parallel and in-line dust-bearing double bubbles in a static liquid were studied to explore the deformation and their influence on the particle removal rate.The results show that the interaction of different sizes of parallel double bubbles in the ascending process has different effects on particle removal,small size bubbles have a higher particle removal rate.The interaction of 8mm-10mm parallel dust-containing double bubbles strengthens the removal of 1?m particles,the 12mm-14mm parallel dust-containing double bubble interaction weakens the removal of 1?m particles.The larger the initial spacing of parallel double bubbles,the higher the removal rate of particles;when the initial spacing of bubbles is small,coalescence will occur,which accelerates the removal of particles.The in-line double bubbles eventually gather and rise as a large-scale bubble,which causes the particle removal rate lower than that of parallel dust-containing double bubbles;the acceleration phenomenon caused by the overlap of the upper and lower bubble centers of the large-size in-line dust-containing double bubbles promotes the remove of particles.