Filtration assembly with backwashing for pressurized fluid system

A filtration assembly for a pressurized fluid system comprising:

• (a) a pressure vessel having a generally cylindrical wall having a closed end and an open end with a removable closure/lid disposed over the open end for forming a fluid pressure chamber in the vessel;
• (b) an inlet port to the chamber provided in the closed end adapted for receiving therethrough fluid to be filtered;
• (c) an outlet port to the chamber provided in the cylindrical wall for discharging filtrate;
• (d) a bulkhead disposed in the chamber intermediate the inlet port and outlet port, the bulkhead removably attached to the cylindrical wall and having an inner array of circumferentially spaced apertures therein and an outer array of circumferentially spaced apertures surrounding the inner array;
• (e) a drain port formed in the closed end of the vessel;
• (f) a tubular backwash arm disposed for rotation in the chamber intermediate the bulkhead and the drain port, the backwash arm having a first open end disposed for, upon rotation of the drain arm, selectively communicating progressively exclusively with each of the apertures in the inner array and a second open end opposite the first open end disposed for, upon rotation of the drain arm, selectively communicating progressively exclusively with each of the apertures in the outer array, the drain arm having a port therein intermediate the first and second ends thereof communicating exclusively with the drain port;
• (g) a motor including a shaft operatively connected through the drain port for effecting, upon selective actuation, rotation of the tubular drain arm;
• (h) a plurality of shroud tubes each having one end thereof sealingly attached over one of the apertures in the inner and outer array and an end of each shroud tube opposite the one end having a seal ring attached thereto;
• (i) a filter media element attached on one end thereof to a cover plate and disposed in each one of the shroud tubes with the cover plate sealed over the seal ring and with the downstream side of each filter media element communicating exclusively through an aperture in the cover plate, wherein the upstream side of each filter media element communicates exclusively with the interior of the respective shroud tube.