Abstract: The present invention concerns un vertical reactor civil and industrial sewage water depuration plant, of the type comprising, in sequence following the flow of water to be depurated: a section (14) of removal of coarse solids which are present in sewage water to be treated, a denitrification basin (18), an oxidation/homogenization basin (20) on the bottom of which a vertical reactor is positioned (22), provided with a plurality of air and oxygen diffusers and with an air lift (23) taking water from the bottom of the vertical reactor (22) and conveying it to a flotation vessel (25) and subsequently to a battery of lamellar packs and from that to a disinfection section (28) and to the outlet, characterised by comprising a second air lift (24) taking water from the vertical reactor (22) at an intermediate height and conveying it to said flotation vessel (25) or to a different flotation vessel (25) and from this to said battery of lamellar packs and subsequently to said disinfection section (28) and to the outle