气浮过程中油滴与气泡相互作用的数值模拟研究
首发时间:2012-12-19
摘要:气体浮选法是一种广泛应用于含油废水净化领域的水处理技术。本文首先分析了分散相液滴在水中的受力情况和上升速度的影响因素。然后,运用fluent软件与VOF模型模拟了气泡在水中的上升过程,研究了气泡的变形和上升速度,研究发现:气泡主要依靠表面张力来维持形状,而粘度比和密度比对于变形基本没有影响;气泡的上升速度主要受粘度比和密度比影响,粘度比越大,上升越慢,密度比越大,上升越快。随后,模拟了气浮过程中气泡和油滴在水中相互作用的过程,对油滴在气泡表面的扩散情况进行了研究,研究表明:只有当热力学扩散系数为正时,油滴才能在气泡表面扩散,形成粘附关系,由气泡带着油滴上升;油滴与气泡的粒径差别过大时,两者就无法形成稳定的粘附关系。
关键词: 化工过程机械 含油废水 油水分离器 气浮 热力学扩散系数 表面张力
For information in English, please click here
Numerical Simulation Study of the Interaction of Bubble and Oil Drop in the Gas Floating Process
Abstract:Gas flotation is widely used in oily waste water purification. Firstly, this paper analysed the force situation and influencing factor to ascensional velocity of the dispersed phase droplet in the water.Then, the software Fluent and VOF multiphase model were used to simulate the rising process of bubbles in the water. Deformation and rising velocity of the bubbles are the objects to study, research finds that bubbles rely on the surface tension for shape maintaining, and the viscosity ratio and density ratio have less impact to deformation; the rising velocity is mainly affected by viscosity ratio and density ratio, the greater the viscosity ratio, the smaller the speed, the greater the density ratio, the bigger the speed. Furthermore, the interaction of bubble and oil drop in the gas floating process was simulated in the water. The diffusion conditions of oil droplets on the bubble surface have been analysed. The research results show that a positive thermodynamic diffusion coefficient is necessary for oil droplets' diffusion. Only in this condition, could an adhesion relationship form, and the bubbles could rise with oildroplets; if the size difference between bubble and oil droplet is too large, no stable adhesion relationship could form.
Keywords: chemical process equipment oily wastewater oil-water separator flotation thermodynamic diffusion coefficient surface tension
论文图表:
引用
No.****
同行评议
共计0人参与
勘误表
气浮过程中油滴与气泡相互作用的数值模拟研究
评论
全部评论0/1000