Suspended particle size distribution and the performance of deep bed filters

The paper examines the importance of suspended particle size distribution in deep bed filtration. Experiments were conducted with suspensions of different size distributions. The changes in total concentration, concentrations of particles of different sizes and the headloss were observed. The suspension with the largest mean particle size gave the greatest removal. It was also observed that the size distribution changed with depth and time, and this was shown to be crucial in understanding filter behaviour. It was concluded that in modelling filter performance it is not sufficient to use the mean characteristics of the influent suspension. Some evidence was found for the interaction between particles of different sizes, and the particle size distribution also affects the distribution of deposit throughout the bed.