Surface coverage of filter medium in deep bed filtration: Mathematical modeling and experiments

This paper highlights the importance of surface coverage in modeling the re moval of particles in deep bed filtration. A model that considers the satur ation of sites on which particle deposition occurs is used. Experimental re sults obtained with monodispersed suspensions of 0.46 and 0.816 mu m latex particles at different influent concentrations and ionic strengths were use d to calculate the fraction of filter grain surface (beta(1)) on which actu al particle deposition occurs. This will be useful in evaluating the filter performance in terms of the utilization of available surface area of the f ilter medium. Further, the level of dendrite formation of particles on filt er grains during filtration is expressed in terms of beta(1) and the specif ic surface coverage, theta(T) (the fraction of a filter grain surface that is covered by particles at time T, assuming that the filter grain is covere d by a monolayer of particles). This can be used to compare the contributio n of deposited particles in the removal efficiency of deep bed filtration f or suspensions with different physical and chemical characteristics.