DESCRIZIONE
Injector for mixing of gas-enriched liquid into flowing liquid, whereby the device comprises an inlet (10), and an outlet means (12) for the gas-enriched liquid arranged to be mounted into a pipe (11) with the flowing liquid. The outlet means (12) is provided with one or more outlet apertures (13) through which the gas-enriched liquid can flow. A piston (14) is arranged movable within the outlet means (12) between a closed position where it blocks all flow of gas-enriched water through the outlet apertures (13), an intermediate position where the piston (14) opens up for larger flow area (13) for flow of gas-enriched liquid, and an open position where the gas-enriched liquid can flow out through all flow area in the outlet apertures (13).