High efficiency backwash shoe

A method for cleaning rotating filter media by backwash comprising the steps of:

• dividing said rotating filter media into a plurality of generally concentric bands;
• placing at least one backwash shoe in fluid communication with said rotating filter media, said backwash shoe having at least one orifice slot;
• positioning said at least one orifice slot on said backwash shoe such that the ratio of orifice area to filter area is substantially equal for each of said concentric bands;
• and
• applying a force to said backwash shoe such that a portion of the filter media passing said at least one orifice slot is drawn into said slot.

An apparatus for cleaning rotating filter media by backwash comprising:

• a backwash shoe in fluid communication with a source of suction pressure;
• at least three orifice slots positioned on said shoe, said slots defining an orifice area;
• said slots positioned on said shoe such that a portion of said filter media is drawn into said slots when said suction pressure is applied to said shoe;
• said slots positioned on said shoe such that the ratio of filter area cleaned per applied orifice area is substantially equal across said filter;
• said slots positioned on said shoe such that a first slot occupies an area extending outward from the inner portion of said rotating filter, and such that second and third slots, generally parallel to each other, extend outward from the outer limit of said first slot.