Abstract: An apparatus for wasting flocculant sludge from a clarifier is provided including a wasting pipe fluidly connectable to a waste conduit, a manifold fluidly connectable to the wasting pipe, an upper header for collecting the flocculant sludge fluidly connectable to the manifold, a return sludge pipe fluidly connectable to a return sludge well, a lower header for collecting settled sludge fluidly connectable to the return sludge pipe, and a drive mechanism for rotating the upper header and the lower header about a center axis. A wastewater treatment system is provided including the clarifier fluidly connectable to a source of a mixed liquor and the apparatus for wasting flocculant sludge. A method of separating settled sludge from a clarifier is provided including withdrawing flocculant sludge and withdrawing settled sludge. A method of retrofitting a clarifier is also provided including providing the manifold, the upper header, and the drive mechanism.

Abstract: An apparatus for wasting flocculant sludge from a clarifier is provided including a wasting pipe fluidly connectable to a waste conduit, a manifold fluidly connectable to the wasting pipe, an upper header for collecting the flocculant sludge fluidly connectable to the manifold, a return sludge pipe fluidly connectable to a return sludge well, a lower header for collecting settled sludge fluidly connectable to the return sludge pipe, and a drive mechanism for rotating the upper header and the lower header about a center axis. A wastewater treatment system is provided including the clarifier fluidly connectable to a source of a mixed liquor and the apparatus for wasting flocculant sludge. A method of separating settled sludge from a clarifier is provided including withdrawing flocculant sludge and withdrawing settled sludge. A method of retrofitting a clarifier is also provided including providing the manifold, the upper header, and the drive mechanism.

Abstract: An apparatus for wasting flocculant sludge from a clarifier is provided including a wasting pipe fluidly connectable to a waste conduit, a manifold fluidly connectable to the wasting pipe, an upper header for collecting the flocculant sludge fluidly connectable to the manifold, a return sludge pipe fluidly connectable to a return sludge well, a lower header for collecting settled sludge fluidly connectable to the return sludge pipe, and a drive mechanism for rotating the upper header and the lower header about a center axis. A wastewater treatment system is provided including the clarifier fluidly connectable to a source of a mixed liquor and the apparatus for wasting flocculant sludge. A method of separating settled sludge from a clarifier is provided including withdrawing flocculant sludge and withdrawing settled sludge. A method of retrofitting a clarifier is also provided including providing the manifold, the upper header, and the drive mechanism.

Abstract: In an orbal wastewater treatment process including a plurality of concentric, annular basins or channels having surface aeration means, wastewater and recycled activated sludge are mixed in a first channel by a combination of the surface aeration means and introducing an oxygen-containing gas such as air into the lower portion of the zone under conditions which produce a complete mix reaction and sufficient oxygen is supplied to meet the biological oxygen demands of the mixed liquor. The gas is introduced, preferably by a plurality of fine bubble membrane diffusers, in the form of fine bubbles having a diameter of less than about 4 mm. The mixed liquor is sequentially oxidized in second and third channels by a combination of surface aeration means and introducing an oxygen-containing gas into the lower portions of the channels, preferably by fine bubble membrane diffusers.

Abstract: Wastewater and recycled activated sludge are homogeneously mixed in a first aeration zone by injecting an oxygen-containing gas such as air into the lower portion of the zone under conditions which produce a complete mix reaction and sufficient oxygen is supplied to meet the biological oxygen demands of the mixed liquor. The gas is introduced, preferably by a plurality of fine bubble membrane diffusers, in the form of fine bubbles having a diameter less than about 4 mm. The bubbles provide both the mixing to keep solids in suspension and the oxygen required to maintain the overall dissolved oxygen content in the first aeration zone as close to 0 as possible. The mixed liquor is sequentially contacted with an oxygen-containing gas in second and third aeration zones under conditions which produce a complete mix reaction, preferably by fine bubble membrane diffusers, clarified and a portion of the settled sludge is recycled to the first aeration zone.