Abstract: The invention concerns a flotation cell (1; 30) for purifying fibrous suspensions through the dispersion of air microbubbles (22), comprising: a container (2; 31); feed pipes (4; 34) for conveying the suspension (3) into the container (2; 31); means (5; 35) for intercepting the purified suspension; means (6) for extracting the purified suspension; means (7) for discharging the foams created by the impurities contained in the suspension (3); rotary vanes (19; 36) arranged inside the container (2; 31). The cell (1; 30) comprises air dispersers (10; 32; 42) for generating air microbubbles (22) and dispersing them in the suspension (3), in each one of which it is possible to identify one rotor (11; 45) with axial flow associated with driving means (12; 47) and one duct (13; 40; 46) for conveying external air at the level of the rotor (11; 45).

Abstract: A propeller for stirring solid-in-liquid suspensions inside a treatment tank is disclosed, comprising a generally axial element consisting of at least a blade with helical development and a generally radial element consisting of a plurality of vanes with generally radial development. Said elements belong to a single central shaft defining a longitudinal rotation axis along which said elements are coaxially arranged one after the other.