Calculation model of uniform media filtration capacity

Filtration is an efficient method for turbidity removal and widely used for water and gas purification. The process of filtration is complicated, and although the basic principles concerning filtration were brought forward decades ago, there is a gap between the theories and their application. Filtration is still an active field for theoretical and experimental research, and there is plenty of room for improvement in this area. In this paper, through the analysis of the uniform media filtration, the capillary model is used to determine the flow pattern in the packed bed, and then the fluid shear force distribution in the capillary is formulated. The physical-chemical forces including van der Waals attraction force, electric double-layer force, Born repulsion force and structural force between the particle and the capillary wall are calculated by analytical equations. By equilibrium analysis of the forces acting on a particle adhered on the capillary wall and appropriate simplification, the analytical equation of the porosity in the saturated filter bed is obtained, from which the maximum entrapment capacity during the filtration process can be achieved. Moreover, the filtration capacity under certain operations are also presented and discussed.