Tertiary wastewater filtration using inclined filter media and internal reverse flow backwashing of filter disks

Abstract

A wastewater tertiary media filtration system capable of enhancing filtration performance while including backwashing capabilities that eliminate turbidity spikes by using compressed fluid injected to the interior of submerged includes a filter tank having an inlet and an outlet with a plurality of pile cloth media filter disks disposed in generally parallel relation between the inlet and outlet. Each filter disk preferably includes opposing filter panels disposed in generally parallel spaced relation and supported by a frame. The filter disks may be angularly disposed at approximately 55-degrees relative to horizontal so as to maximize settlement velocity in accordance with the advantages of inclined plate technology. Backwashing is primarily accomplished by injecting compressed fluid (such as air) to the interior of each filter disk assembly whereby accumulated solids are blown off of the cloth filter media by reverse flow. Injecting a compressed fluid medium into the interior of each filter disk assembly increases the internal pressure within each filter disk thereby avoiding turbidity spikes associated with externally applied suction backwash systems of the background art.