Abstract: A filter apparatus in which a generally horizontal bed of filter material is supported in a tank on a porous support above the bottom of the tank and is divided by spaced partitions into individual filter cells above the support and individual filter compartments below the support, and a carriage is mounted for movement along the filter bed and has a collector hood that moves along the top of the bed to collect backwash effluent therefrom and a backwash head arranged to direct backwash fluid into the compartments below the porous support to sequentially backwash the filter cells. A cell scavenging head is mounted on the carriage for movement along the filter bed and arranged to sequentially withdraw fluid from each filter compartment and down-flow scavenge and rinse the associated filter cell subsequent to backwashing of each filter cell.

Abstract: A floating downflow mixer including a float having a central float passage and a pump casing mounted on the float with its upper end spaced below the float to provide an intake at the underside of the float. A drive motor is mounted on top of the float and has an integral shaft extension extending downwardly through the float passage and a propeller mounted at its lower end in the pump casing. A shaft stabilizer tube is supported on a mounting plate attached to the top of the float and extends downwardly through the float with an anti-deflection bearing at its lower end surrounding the shaft and having a running clearance therewith to inhibit deflection of the shaft. The mounting plate seals the float passage between the stabilizer tube and float and a mechanical rotary seal seals the interface between the stabilizer tube and shaft to prevent entrance of air to the anti-deflection bearing and propeller.