The invention relates to a mixing chamber in which a first liquid comes into contact with a second liquid, and a gas injection device designed to inject a gas into the mixing chamber, wherein the gas injection device comprises: a gas source to provide the gas at a predetermined pressure, and a metering unit to limit the gas provided by the gas source to a predetermined flow rate, wherein the metering unit is in contact with the mixing chamber on a gas outlet side of the metering unit, wherein the gas outlet side of the metering unit comprises an elongated gap, wherein the gas passes out of the metering unit into the mixing chamber via the elongated gap, and wherein the gas passes out of the metering unit into the mixing chamber.

A device for generating gas bubbles in a liquid in a container includes a rotatable gas-permeable hollow shaft arranged in a container, gassing discs arranged on the hollow shaft and spacers arranged between the gassing discs, gassing discs and spacers being arranged alternately on the hollow shaft in gas-tight contact with one another, a feed line for a compressed gas into the interior of the shaft, having a centered opening (O) for receiving said shaft and at least two chambers, said chambers being equally spaced around said centered opening, where said centered opening and said chambers at least partially overlap, where the centered opening and the chambers are in communication with one another at least in the overlap region, so that the compressed gas can flow from shaft into in each case a chamber of the spacer and enter the gassing discs from the chamber of the spacer.

A mixing chamber in which a first liquid comes into contact with a second liquid, and a gas injection device designed to inject a gas into the mixing chamber, wherein the gas injection device includes: a gas source to provide the gas at a predetermined pressure, and a metering unit to limit the gas provided by the gas source to a predetermined flow rate, wherein the metering unit is in contact with the mixing chamber on a gas outlet side of the metering unit, wherein the gas outlet side of the metering unit includes an elongated gap, wherein the gas passes out of the metering unit into the mixing chamber via the elongated gap, and wherein the gas passes out of the metering unit into the mixing chamber.