Filtering device for the clarification of liquids

A filtering device for clarification of waste water, comprising:

• an open tank provided with side walls, a base, and a floor positioned in parallel spaced relation to the base;
• the floor incorporating nozzles for permitting fluid communication between spaces located above and below the floor;
• first parallel spaced vertical partitions extending above the floor and forming an axial channel extending the length of the tank that serves as a conduit for removing wash water during a cleaning phase;
• second parallel spaced vertical partitions extending below the floor that serve as conduits for removal of filtered waste water during a filtering phase and also to introduce pressured water and air to the nozzles during a cleaning phase said second parallel spaced vertical partitions having a watertight partition therebetween defining two adjacent axial channels extending the length of the tank;
• filter material supported by the floor and contained between the side walls and outward surfaces of the first vertical partitions;
• The first and second partitions and said watertight partition effectively dividing the filtering device into two independent cells;
• side channels formed on opposite side walls of the tank for supplying waste water to each cell of the filtering device, wherein each channel includes
• (a) an upwardly inclined wall section extending from the side wall of the tank and including calibrated lower orifices through which waste water flows into the tank at controlled rates during a filtering phase, and through which wash water flows during a cleaning phase;
• (b) an upwardly extending vertical wall section extending from the inclined wall section of the tank and including upper calibrated orifices through which waste water flows into the tank at controlled rates.
• (c) the calibrated orifices in the side channels subjecting each cell to equal distribution of waste water over the entire length of each cell, during a filtering phase, and equal distribution of wash water through the side channels during the cleaning phase.