1. Field of the Invention
The present invention relates to fluid filtration, and particularly to a filtration system including a vessel containing a media through which a fluid is filtered. More particularly, the present invention relates to a distributor/collector system positioned within the vessel for directing the flow of fluid through the media bed.
2. Description of the Related Art
Conventional distributor/collector systems are positioned in a vessel with the collector spaced-apart from the distributor and positioned downstream of the distributor. A typical distributor/collector system includes an upper header as part of the distributor and a lower header as part of the collector, each running generally transversely through the vessel and generally parallel to each other. Both the upper header and lower header include a series of laterals extending radially away from the header and generally in a plane perpendicular to a longitudinal axis of the vessel. In a typical distributor/collector system, a fluid (e.g. water, etc.) enters the vessel and flows down the upper header generally along a diameter of the vessel and then away from the upper header through the upper laterals. From there, the water flows through a media bed below the upper header and into the lower laterals below the media bed. The water then is collected by the lower laterals and carried back toward the center of the vessel to the lower header, which sits generally along a diameter of the vessel, like the upper header. Finally, the water flows down the lower header and exits the vessel on generally the same side of the vessel as it entered the vessel.
In conventional distributor/collector systems, the flow may not be uniform throughout the media bed. The time it takes water to flow through the system at certain points within the media bed may vary from the time it takes water to flow through the system at other points within the media bed. Water which flows out the upper laterals close to the upper header also flows into the lower laterals close to the lower header and, therefore, travels a shorter distance through the system than water which travels out the upper laterals at a distance away from the upper header and into the lower laterals at a point distant from the lower header. These various flow paths through a typical system create various levels of flow through the system. A distributor/collector apparatus that provides even flow throughout the system and, thus, a high distribution efficiency (the ratio between the lowest flow and highest flow that exits the distributor or enters the collector) would be welcomed by users of filtration systems utilizing such a distributor/collector.