High Rate Filtration System

A process for filtering a fluid to remove particles therefrom, said process comprising the steps of:

• a) passing fluid containing particles through a filter bed comprising a compressible filtration media;
• b) compressing the filtration media to define a porosity gradient in the filter bed proceeding progressively from more porous to less porous in the direction of the flow of fluid so that filtration proceeds at a filtration flow rate in a direction from a more porous to a less porous filter bed;
• c) periodically expanding the filter bed;
• d) passing filter media washing fluid through the expanded filter bed to wash the filtration media at a washing fluid flow rate that is from about 1 to 6 percent of a filtration flow rate established in step (b).

A process for filtering waste water to remove suspended solids therefrom, said process comprising the steps of:

• a) passing influent waste water through a filtration bed in an axial flow direction, the filtration bed comprising a compressible filtration media;
• b) compressing the filtration media to define a porosity gradient in the filter bed proceeding from more porous to less porous filtration media in the axial flow direction;
• c) removing progressively smaller solids particles from the waste water as filtration proceeds from a more porous to a less porous media;
• d) establishing a substantially uniform rate of solids removal;
• e) periodically expanding the filter bed;
• and
• f) washing the expanded filter bed in influent waste water to clean the filtration media.