Self-cleaning filtration system with minimal waste generation for water purification applications

A self-cleaning rigid screen type water filtration system for treating water containing solids, the system comprising:

• a generally cylindrical filter vessel having a vessel interior which houses an elongated filter array comprising a plurality of rigid tubular screen type filter elements having porous exterior and interior sidewalls, the interior sidewalls forming interior axial bores, the filter elements being closed at a bottom end thereof and open at a top end thereof;
• an unfiltered water inlet to the vessel for providing a feed stream of slurry water containing solids to be filtered;
• wherein the unfiltered water is received in a bottom region of the vessel interior and travels upwardly where it contacts the exterior sidewalls of the filter elements at a sufficient pressure so that the fluid of the slurry passes inwardly through the sidewalls of the tubular filter elements, with a majority of the solids within the slurry being collected as a cake on the exterior sidewalls, without substantial intrusion into the interior axial bore of the filter elements;
• an elongated spray bar rotatably mounted for rapid rotation within each of the filter elements, each of the spray bars having a plurality of slots cut along the length thereof in a predetermined pattern, the spray bars having an internal bore which is in communication with a source of high pressure air and high pressure water for providing a brief pressure pulse of high-pressure air or water radially outward, which causes the spray bar to rotate and spray air or water outwardly from the spay bar slots and through the interior sidewalls of the porous filter elements to dislodge the collected cake from the exterior wall surfaces.