Abstract: In grid-type aeration systems with diffusers mounted and spaced longitudinally along air distribution conduits that are submerged in wastewater and secured to and above the floors of aeration tanks, such conduits are provided with couplings having first and second matingly compatible coupling sections of synthetic polymeric material adapted for relative rotation with respect to each other, at least one locking projection having a fixed position with respect to one of the coupling sections, and a locking receptacle array including locking receptacles having a fixed position with respect to the other coupling section. The projection and receptacles are relatively moveable in the coupling for motion from a non-engaged condition to an engaged condition during make up of the coupling.

Abstract: This disclosure relates to aeration, especially biological treatment of wastewater with fine pore diffusers and in situ cleaning of these diffusers with liquid and/or gaseous cleaning fluids supplied to the diffusers through cleaning fluid channels that respectively have separate and direct connections to plural diffusers. Aeration and cleaning of fine pore diffusers is described in which cleaning fluid is conducted from a source of such fluid to a multiplicity of diffusers via a flow path which is separate from a flow path which conveys aeration gas to the diffusers. Methods of fabricating aeration gas distribution assemblies are also disclosed. One such method involves securing to an aeration gas distribution conduit at least a portion of a cleaning fluid distribution channel which includes one or more cleaning fluid distribution conduits and further includes connectors coupled to the cleaning fluid distribution conduits.

Abstract: This disclosure relates to aeration, especially biological treatment of wastewater with fine pore diffusers and in situ cleaning of these diffusers with liquid and/or gaseous cleaning fluids supplied to the diffusers through cleaning fluid channels that respectively have separate and direct connections to plural diffusers. Aeration and cleaning of fine pore diffusers is described in which cleaning fluid is conducted from a source of such fluid to a multiplicity of diffusers via a flow path which is separate from a flow path which conveys aeration gas to the diffusers. Methods of fabricating aeration gas distribution assemblies are also disclosed. One such method involves securing to an aeration gas distribution conduit at least a portion of a cleaning fluid distribution channel which includes one or more cleaning fluid distribution conduits and further includes connectors coupled to the cleaning fluid distribution conduits.