Characteristics of particle removals in a compressible media filter system

Abstract

The ability to adjust the properties of the filter medium by altering the degree of the medium compression is important because the different porosities in media affect the ideal filter performance according to the properties of influent wastewater. This study therefore focused on the particle size distribution (PSD) of compressible media filter (CMF) effluents depending on the compression ratio (0-30%) and the filter bed depth (Layers 1-5) in order to evaluate the CMF performance. The results showed that the removal efficiency for particles larger than 10 mu m was more than 90% while that for particles smaller than 10 mu m was less than 85% of removal efficiency. From the power law fit, substantial decreases in the number of large-sized particles were observed in the PSD. Particle removal efficiencies increased along with the average compression ratio increase. Furthermore, the results demonstrated that each layer in the bed had a different role in the filter performance, and it was found that a filter bed of about 0.45-0.60 m would be needed for the production of the desired effluent quality in this study. The detachment phenomenon was observed in particles larger than 5 mu m, especially in 5-15 mu m particles.