It is a scrubber for the treatment of the air by means of chemical reaction with specific reagent. Generally it is realized in 2 sections so to increase the efficiency and grant the complete respect of rules.
Section 1 - Venturi: the polluted air comes aspired in the scrubber where, for effect of the turbulence created in the throat by the high speed, a cleaning effect comes out thanks to the washing solution sprayed.
Section 2 - Venturi: after the Venturi, the air passes to the washing tower where it is washed again in countercurrent with low speed and with one great contact surface.
After this treatment the air goes in the atmosphere by the integrated fan. In the tower are install some demisters (alveolar packages, drop separators) in order to eliminate the dragging effect.