Abstract: For the purpose of introducing or removing gases into liquids or out of liquids, in particular substrates being subject to a biological conversion, rotating plates (3) are immersed into the liquid phase. The plates (3) are rotatably arranged within a tubular receptacle (1) and arranged in at least one axial section such that they alternately include with the axis (2) of rotation extending in parallel relation to the liquid level an angle of more and less than 90.degree.. Shut-off valves (9) for the gas supply conduit and for the gas discharge conduit are connected to the tubular container (1). The plates (3) are provided with a rough surface and are preferably formed of a porous, in particular foamed, material, wire mesh, wire grating or expanded metal sheet. (FIG.

Abstract: The apparatus for removing liquid films floating on liquids, in particular oil films floating on water, has a plurality of rotatably supported plates (3) which are driven for rotation around an axis (2) and which are immersed into the liquid level. The oil entrained by the surface of the plates (3) on emersion from the liquid level is stripped by means of strippers (4) and supplied to a collecting launder (5).

Abstract: Apparatus for continously producing ethanol from fermentable sugar solutions comprises horizontal, tubular mixing and separating vessel having internal rotating plates inclined relative to the horizontal axis of rotation. The yeast charged to the vessel is extracted from the vessel and is subjected to a multi-stage fermentation within horizontal fermentation vessels. Within the fermentation vessels there are again arranged inclined rotating plates. The ethanol is separated in a gaseous phase, the pressure being reduced stepwise in succeeding fermentation vessels tubes.

Abstract: The apparatus for continuously separating liquid phases of different density consists of a separating basin (1) within which are arranged partition walls (5) for being lifted and lowered and for being moved one in direction to the other or for being swivelled. Swivelling of the partition walls (5) is effected about an eccentrically arranged axis (7) such that during the swivelling movement the partition walls (5) are simultaneously lifted or lowered. The partition walls (5) can be driven by push rods (8) and thus be swivelled in the contrary sense. When swivelling the partition walls (5) in one direction, the liquid level is lifted in the chamber defined between the partition walls and is lowered in the adjacent chamber, noting that the portion having the lower specific gravity flows over the upper edge, assuming a lower level, of the one partition wall in one direction (11) and that the proportion having the higher specific gravity flows in direction of the arrow (12), i.e.