纤维束滤床直接过滤动力学模型

应用单位床单元概念和圆柱池多孔介质模型,推导得到上向流纤维束滤床初始过滤系数表达式,其中收集效率由操作参数构成的无量纲数群关联得到,并据此探讨了悬浮颗粒的去除机理.假设过滤系数是滤床比表面积和空隙流速的函数,推得过滤系数的半经验公式,进而得到了过滤动力学模型.模型中的参数被赋予了明确的物理意义,且能反映操作条件对动力学行为的影响.在不同尺寸悬浮颗粒和不同表观滤速下进行了过滤实验.模型预测值与实验结果比较表明,二者具有一致性.

Dynamics model of direct filtration with fibrous bundle media

On the basis of unit bed element and cylindrical cell model, an initial filtration coefficient expression of direct filtration with upward flow fibrous bundle media was presented. The collection efficiency was determined by correlating dimensionless groups consisting of operating parameters, from which removal mechanisms of suspended particles were discussed. A semi - empiric expression of filter coefficient was establishing under the assumption that filter coefficient is the function of the specific area and the interstitial velocity. Then a dynamics model was developed, the parameters not only had immediate physical interpretation, but also reflected that the operating conditions have effect on the dynamic behavior. And the experiments were conducted under the conditions of suspended particles of different sizes and superficial filtration velocities. The comparison between model predictions and experimental data indicated that both agreed reasonably well.