Abstract: The invention relates to a device for generating gas bubbles in a liquid in a container, including at least one rotatable hollow shaft arranged horizontally in at least one container; at least one gassing disc arranged vertically on the at least one hollow shaft; and at least one feed line for supplying at least one compressed gas to the interior of the at least one hollow shaft, said compressed gas being brought into the feed line and hollow shaft directly, without a liquid carrier.

Abstract: The present invention relates an apparatus for cleaning water, in particular precleaning seawater, including at least one tank for receiving water containing at least one flocculating agent for separating organic and possibly biological constituents contained in the water. The at least one tank includes at least one contact zone K for contacting the water containing the flocculating agent with at least one gas, in particular air, and at least one separation zone S for separating the flocculated organic constituents buoyed up by the gas. At least one gassing unit is arranged in the at least one contact zone K and at least one filtration unit is arranged in the at least one separation zone S. The at least one gas is injected via the at least one gassing unit without using a liquid carrier.