FIELD OF THE INVENTION

The present invention relates to rotary disc filters, and more particularly to rotary disc filters and their backwashing systems.

BACKGROUND OF THE INVENTION

A rotary disc filter employs a backwash system that is periodically actuated to backwash the filter media and dislodges suspended solids disposed on the inner sides of the filter media. Such backwashing systems employ nozzle support assemblies for supporting nozzles adjacent the filter media. There are a number of disadvantages and drawbacks to conventional nozzle support assemblies. First, in a typical rotary disc filter design, there is provided a backwash manifold that extends along one side of the disc filter. Inner steel pipes connected to the manifold extend into areas between the filter discs. Conventional nozzles and associated nozzle support assemblies are operatively connected to the inner end portions of the inner steel pipes. The inner steel pipes and the associated nozzle support assemblies are quite heavy and place a significant torque on the manifold. Secondly, these nozzle support assemblies typically include multiple parts. The steel pipes have to be drilled to provide openings to emit backwash. Typically, these nozzle support assemblies include welded and screw joints that have the potential to leak. In the end, such conventional nozzle support assemblies are costly and require a significant amount of assembly time.

Therefore, there has been and continues to be a need for a nozzle support assembly design that reduces cost, assembly time, number of parts, joints, seals and reduces potential leakage points.

SUMMARY OF THE INVENTION

The present invention relates to a rotary disc filter having a filter backwash system that includes a nozzle holder configured to support multiple nozzles and configured to be operatively connected to a backwash feed pipe, sometimes referred to as an inner pipe.

In one embodiment, the nozzle holder includes an elongated main conduit having an outer wall and a series of branch conduits projecting outwardly from the outer wall and including terminal end portions. Nozzles are detachably secured to the terminal end portions of the branch conduits.

Further in one embodiment, the nozzle holder is constructed of molded plastic and includes a main conduit having an outer wall and a plurality of branch conduits that project outwardly from the outer wall. The branch conduits include terminal end portions that receive detachable nozzles. In this embodiment, the nozzle holder including the main conduit, outer wall, and branch conduits are all formed into a single piece of molded plastic.

Other objects and advantages of the present invention will become apparent and obvious from a study of the following description and the accompanying drawings which are merely illustrative of such invention.

