Abstract: Described is a gas-introduction device designed to introduce a gas into a liquid. The device comprises at least one gas-feed manifold (10) and a multiplicity of tubular feed-in elements (12) which are open at the free end. Each feed-in element is surrounded by a perforated tubular membrane (14). A gas-supply line in each feed-in element terminates in the vicinity of the membrane. Each feed-in element comprises two support elements (46, 48) extending out from a central element. The central element has a flange which is designed to be fastened to the outside of the gas-feed manifold. A gas-supply line leads from a bore in the gas-feed manifold, via a central line (26) and two branch lines (28) leading off the central line (26), into longitudinal grooves behind the membrane. The central line and the branch lines are located in the central element. The feed-in element is a monobloc construction including the central element and the membrane-support elements.

Abstract: With gas injection equipment used to inject a gas into a liquid the problem exists that the conducting element filled with gas will experience buoyancy. To eliminate this buoyancy, the conducting element is open at its free end and closed at its other end, bearing there a fastening connection permitting its connection to a gas supply distributor. The conducting element is surrounded by a perforated, hose-like membrane, and a gas supply conduit discharges into the area of the membrane. To facilitate fabrication and assembly as well as in order to reduce material consumption, the conducting element is configured in such a way that its gas supply conduit penetrates the fastening connection as an axial blindend bore, and that in the area of the membrane at least one radial discharge is present. A transverse groove preferably extends from the discharge of the gas supply conduit up to the free end of the conducting element, over which transverse groove gas can be uniformly distributed.