Abstract

Disclosed is an apparatus for the intermittent aeration of sewage or sewage-activated sludge mixtures. The apparatus is adapted to be disposed below water level and consists of a horizontal air distributor in the form of a pipe jacket closed tightly at both ends except for an aperture for the air supply, and which, in the area of its two opposite lateral longitudinal edges, includes apertures for the passage of air. The apparatus further includes an elastic air distributing foil covering the apertures for the passage of air and the upper portion of the pipe jacket located between the apertures. The foil is provided with air escape openings which are opened by the air supply to the pipe jacket and closed in case of interruption of the air supply by being sealed against the pipe jacket outside the area of the air passage openings. The apparatus further includes distancing strips located at the two opposite lateral longitudinal edges of the pipe jacket, below the openings for the passage of air and between the pipe jacket and the air distributor foil.