The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 25, 2004
Filed:
Sep. 22, 1997
R. Lee Roberts, Chadds Ford, PA (US);
Mark Kevin Addison, Bear, DE (US);
Andrew Scott Taylor, Drexel Hill, PA (US);
RG Delaware, Inc., Wilmington, DE (US);
Abstract
An improved underdrain block for an underdrain system supporting a filter media bed in a liquid filtration system is provided. The underdrain blocks are preferably made of an extrudable polymeric material that is extruded in relatively long sections to provide light weight, strong, easily manufactured underdrain systems having a lower profile than prior art underdrain blocks. The underdrain block comprises an upper wall, side walls, a lower wall, at least one lateral member between the upper wall and the lower wall, at least two chambers within the underdrain block, each chamber being defined by the lateral member, a plurality of upper orifices in the upper wall of the underdrain block, and a plurality of internal orifices in the lateral member. The underdrain block is substantially greater in longitudinal length than a longitudinal distance between the upper orifices. In one embodiment, the underdrain block has rails situated on the upper wall for engaging extruded members, which in turn, have receiving recesses for receiving a layer of porous filter media. In another embodiment, the underdrain block further comprises an air nozzle for achieving an improved distribution of air through a filter bed during air backwashing.