But spray tower scrubber described in Figure-1 is
the simplest and low-cost wet scrubber system in which
water droplets are introduced at the top of an empty
chamber through atomizing nozzles and fall freely at their
terminal settling velocities counter-currently through the
rising dust particle-gas stream. The dust particles are then
separated from the gas stream and collected in a pool at
the bottom of the chamber. A mist eliminator is usually
placed at the top of the spray tower to remove both excess
clean water droplets and dirty droplets which are very
small and thus are carried upward by the gas flow.