In a wastewater treatment system, a clarifier has a submerged effluent launder, with a sloped, submerged plate that allows clarified liquid to exit through submerged openings. The sloped surface tends to accumulate solids, which can lead to algae growth. Typical internal scum collection system equipment prevents any efficient way to clear the accumulated sludge off the launder surface because of interferences. As disclosed here, a scum discharge area or box is placed external to the clarifier in one embodiment. Scum is wiped from a vertical surface of the launder assembly, above the sloped launder surface, and swept over a scum beach at one position in the clarifier, to drop into a lower trough and the flow out through the clarifier wall to a drop out box or scum discharge area. This allows for a rake-attached, sweeping launder wiper to be moved with the clarifier's rake to remove the accumulation of sludge from the launder's submerged surface, without elaborate moving parts. The sludge is swept back to settle in the clarifier, improving effluent quality by preventing sludge from exiting along with clarified water. In another embodiment the scum discharge box is internal, as a low-profile vertically disposed channel against the inside clarifier wall, leading to an existing scum pipe through the clarifier wall.

An improved clarifier tank having a rake arm assembly with one or more rake arms, a rake arm driveshaft operatively connected to the rake arms and a rake arm drive, and a sump scraper driveshaft, operatively connected to a plurality of sump scrapers and a sump scraper drive.

An improved clarifier tank having a rake arm assembly with one or more rake arms, a rake arm driveshaft operatively connected to the rake arms and a rake arm drive, and a sump scraper driveshaft, operatively connected to a plurality of sump scrapers and a sump scraper drive.

In a wastewater treatment system, a clarifier has a submerged effluent launder, with a sloped, submerged plate that allows clarified liquid to exit through submerged openings. The sloped surface tends to accumulate solids, which can lead to algae growth. Typical internal scum collection system equipment prevents any efficient way to clear the accumulated sludge off the launder surface because of interferences. As disclosed here, a scum discharge area or box is placed external to the clarifier in one embodiment. Scum is wiped from a vertical surface of the launder assembly, above the sloped launder surface, and swept over a scum beach at one position in the clarifier, to drop into a lower trough and the flow out through the clarifier wall to a drop out box or scum discharge area. This allows for a rake-attached, sweeping launder wiper to be moved with the clarifier's rake to remove the accumulation of sludge from the launder's submerged surface, without elaborate moving parts. The sludge is swept back to settle in the clarifier, improving effluent quality by preventing sludge from exiting along with clarified water. In another embodiment the scum discharge box is internal, as a low-profile vertically disposed channel against the inside clarifier wall, leading to an existing scum pipe through the clarifier wall.

An improved clarifier tank having a rake arm assembly with one or more rake arms, a rake arm driveshaft operatively connected to the rake arms and a rake arm drive, and a sump scraper driveshaft, operatively connected to a plurality of sump scrapers and a sump scraper drive.

An improved clarifier tank having a rake arm assembly with one or more rake arms, a rake arm driveshaft operatively connected to the rake arms and a rake arm drive, and a sump scraper driveshaft, operatively connected to a plurality of sump scrapers and a sump scraper drive.

A settling basin of a wastewater treatment system includes a collector chain including chain links having a plurality of side bars, stepped connecting pins configured to join the plurality of side bars and including a first end including a head portion having a cross-sectional area larger than portions of the plurality of side bars through which the stepped connecting pin extends, end caps configured to receive second ends of the stepped connecting pins, and apertures defined in the end caps and second ends of the stepped connecting pins configured to receive a retaining element that holds the end caps in position on the second ends of the stepped connecting pins.

A scum removal system for use with a wastewater treatment clarification tank containing wastewater is provided and includes a debris intake conduit, a debris discharge conduit, and a pump article. The pump article is configured to be in flow communication with the debris intake conduit and the debris discharge conduit, wherein the pump article and debris intake conduit are configured to generate a suction within the debris intake conduit and wherein the debris intake conduit is configured to be located proximate the wastewater. Additionally, the debris intake conduit is sloped downwardly at a debris intake conduit angle β, and the second discharge conduit is sloped downwardly at a debris discharge conduit angle Ω

A scum removal system for use with a wastewater treatment clarification tank containing wastewater is provided and includes a debris intake conduit, a debris discharge conduit, and a pump article. The pump article is configured to be in flow communication with the debris intake conduit and the debris discharge conduit, wherein the pump article and debris intake conduit are configured to generate a suction within the debris intake conduit and wherein the debris intake conduit is configured to be located proximate the wastewater. Additionally, the debris intake conduit is sloped downwardly at a debris intake conduit angle β, and the second discharge conduit is sloped downwardly at a debris discharge conduit angle Ω

A head shaft assembly has a center tube, an end tube, a collector sprocket and a collar. The center tube has drive and driven ends. The center tube has a center tube diameter. The end tube has a key extending longitudinally along an outer surface and inner and outer ends. The key defines a key length and the end tube has an end tube diameter. The collector sprocket is mountable to the end tube and rotationally secured to the end tube by the key. The collar is hollow between a first end and a second end. The center tube diameter is substantially the same as the end tube diameter and the drive end is proximate to the inner end. The drive end and the inner end are positioned within the collar between the first end and the second end. The collar fixes the center tube to the end tube.