Abstract: A filtration system has at least one underdrain lateral, a flume, and at least one metering plate. The metering plate includes a plate member with at least one opening configured to receive liquid or gas therethrough at a first flow rate during a backwash function and is configured to receive liquid or gas therethrough at a second, lower flow rate during filtration. A method of metering gas into a filtration system with a metering plate is also disclosed. The metering plate allows gas to flow into each underdrain lateral at two very different flow rates.

Abstract: An underdrain block for filtering water includes a top wall, a bottom wall, and two side walls connecting the top wall to the bottom wall to define an internal chamber. The bottom wall contains a plurality of orifices that allow liquid and solid materials to enter and exit the internal chamber. An underdrain filtering system can be formed by securing an underdrain lateral, which is formed from one or a plurality of underdrain blocks, to a filter floor. Also included is a method of preparing an underdrain lateral for providing even distribution of backwash water along the underdrain lateral and a method of validating even distribution of backwash water across an underdrain lateral.

Abstract: A filter media retainer has a plate having a first end wall, a second end wall, and a pair of longitudinal sidewalls connected to opposing sides of the first end wall and the second end wall. The plate has a top surface opposite a bottom surface. A plurality of hopper-shaped compartments are formed on the top surface and have a first sloped wall and a second sloped wall angled toward the first sloped wall in a direction from the top surface toward the bottom surface. The plate further has a top sidewall on the top surface of the plate separating adjacent hopper-shaped compartments from each other. The plate further has at least one first slot extending through at least one of the first sloped wall and the second sloped wall, and at least one second slot extending through the top sidewall.

Abstract: A method of installing a filter underdrain system includes: positioning a grout pad on a filter floor; positioning an underdrain block onto the grout pad such that the grout pad is displaced when the underdrain block is positioned on the grout pad; and inserting filler grout around the underdrain block.

Abstract: A filtration system having an underdrain block and an underdrain wall adaptor. The underdrain wall adaptor includes a vertical end and horizontal base. The vertical end extends from a top wall to a bottom wall of an underdrain block and mates with an end portion of an underdrain block to secure the underdrain wall adaptor to the underdrain block. The horizontal base extends from the vertical end. The invention also includes a method of installing an underdrain wall adaptor. The underdrain wall adaptor controls air and water passage between the flume and the underdrain.

Abstract: A filter media retainer has a plate having a first end wall, a second end wall, and a pair of longitudinal sidewalls connected to opposing sides of the first end wall and the second end wall. The plate has a top surface opposite a bottom surface. A plurality of hopper-shaped compartments are formed on the top surface and have a first sloped wall and a second sloped wall angled toward the first sloped wall in a direction from the top surface toward the bottom surface. The plate further has a top sidewall on the top surface of the plate separating adjacent hopper-shaped compartments from each other. The plate further has at least one first slot extending through at least one of the first sloped wall and the second sloped wall, and at least one second slot extending through the top sidewall.

Abstract: An underdrain block for filtering water includes a top wall, a bottom wall, and two side walls connecting the top wall to the bottom wall to define an internal chamber. The bottom wall contains a plurality of orifices that allow liquid and solid materials to enter and exit the internal chamber. An underdrain filtering system can be formed by securing an underdrain lateral, which is formed from one or a plurality of underdrain blocks, to a filter floor. Also included is a method of preparing an underdrain lateral for providing even distribution of backwash water along the underdrain lateral and a method of validating even distribution of backwash water across an underdrain lateral.

Abstract: A method of installing a filter underdrain system includes: positioning a grout pad on a filter floor; positioning an underdrain block onto the grout pad such that the grout pad is displaced when the underdrain block is positioned on the grout pad; and inserting filler grout around the underdrain block.

Abstract: A method of installing a filter underdrain system includes: positioning a grout pad on a filter floor; positioning an underdrain block onto the grout pad such that the grout pad is displaced when the underdrain block is positioned on the grout pad; and inserting filler grout around the underdrain block.

Abstract: A filtration system has at least one underdrain lateral, a flume, and at least one metering plate. The metering plate includes a plate member with at least one opening configured to receive liquid or gas therethrough at a first flow rate during a backwash function and is configured to receive liquid or gas therethrough at a second, lower flow rate during filtration. A method of metering gas into a filtration system with a metering plate is also disclosed. The metering plate allows gas to flow into each underdrain lateral at two very different flow rates.

Abstract: A filtration system having an underdrain block and an underdrain wall adaptor. The underdrain wall adaptor includes a vertical end and horizontal base. The vertical end extends from a top wall to a bottom wall of an underdrain block and mates with an end portion of an underdrain block to secure the underdrain wall adaptor to the underdrain block. The horizontal base extends from the vertical end. The invention also includes a method of installing an underdrain wall adaptor. The underdrain wall adaptor controls air and water passage between the flume and the underdrain.

Abstract: An underdrain flume plate for use in a filter including at least one central opening having an upstanding flange to interface with a cut-out in an underdrain lateral to form a passageway for connecting the lateral to the flume. The flume plate may also include at least one raised channel at each end of the plate with a solid or cut-away top surface, and/or holes and/or slots for connection of the flume plate to anchor rods and may be configured to overlap one another when placed side by side. The present invention also includes a method of installing underdrain laterals in a filter, including arranging a grid of anchor rods on a filter floor such that anchor rods are provided on both sides of the flume, and providing at least one underdrain flume plate adapted for attachment to the anchor rods such that the flume plate covers the flume.

Abstract: A flush apparatus for a filter underdrain system can include a fluid connection member having a body with a first end and a second end, the first end adapted to connect to a fluid source; a top plate connected to the second end of the fluid connection member; and a bottom plate opposing the top plate and adapted to engage a top portion of an underdrain system, the bottom plate having orifices that distribute fluid to the underdrain system to transport materials through the underdrain system. A system for cleaning unwanted materials from a water or waste water treatment filter and a method of transporting unwanted materials through an underdrain system are also disclosed.

Abstract: A method of installing a filter underdrain system includes: positioning a grout pad on a filter floor; positioning an underdrain block onto the grout pad such that the grout pad is displaced when the underdrain block is positioned on the grout pad; and inserting filler grout around the underdrain block.

Abstract: A dual parallel underdrain lateral for use in a filtration system having a filtration media includes a primary conduit extending along the underdrain lateral, which has a plurality of metering orifices for providing gas and liquid thereby; a secondary conduit, where the secondary conduit has a plurality of dispersion apertures in an upper side thereof to deliver the gas and liquid from the secondary conduit to the filtration media; and at least one gas conduit extending along the underdrain lateral, where the at least one gas conduit is connected to a gas source and is configured to provide the gas from the gas source directly to the primary conduit, or the secondary conduit, or any combination thereof.

Abstract: A media retainer assembly for retaining filter media in a filter assembly includes a top plate for supporting the filter media, the top plate having a top surface, a bottom surface and a plurality of openings extending therethrough; a bottom plate having a top surface and a plurality of openings extending therethrough; and scouring media, the scouring media being adapted to abrade the surfaces of the top and bottom plates. The top plate is connected to the bottom plate such that the top surface of the bottom plate is spaced from the bottom surface of the top plate to define at least one chamber between the top plate and the bottom plate. The top surface of the top plate is in fluid communication with the chamber via the openings in the top plate. The scouring media is supported by the bottom plate within the at least one chamber.

Abstract: A media retainer assembly for retaining filter media in a filter assembly includes a top plate for supporting the filter media, the top plate having a top surface, a bottom surface and a plurality of openings extending therethrough; a bottom plate having a top surface and a plurality of openings extending therethrough; and scouring media, the scouring media being adapted to abrade the surfaces of the top and bottom plates. The top plate is connected to the bottom plate such that the top surface of the bottom plate is spaced from the bottom surface of the top plate to define at least one chamber between the top plate and the bottom plate. The top surface of the top plate is in fluid communication with the chamber via the openings in the top plate. The scouring media is supported by the bottom plate within the at least one chamber.

Abstract: An adjustable anchor rod arrangement for use with an underdrain system that includes the a pair of spaced apart legs and an elongated member adjustably attached to the legs, wherein the legs are adjustable along a longitudinal axis of the elongated member and the elongated member is adjustable along a longitudinal axis of the legs.

Abstract: The present invention is related to a method and system for cleaning a media support structure in a filter cell in a liquid filter system, wherein a cleaning solution does not significantly enter a filter media zone. The method comprises supplying a cleaning solution to a filter cell to a level sufficient to submerge the media support structure, but not to significantly enter the filter media zone. Additionally, the cleaning solution level is monitored to ensure the cleaning solution does not significantly enter the filter media zone. Alternatively, the cleaning solution may be continuously recirculated and reintroduced to the filter cell during the cleaning operation.