Page 297 - APPLIED PROCESS DESIGN FOR CHEMICAL AND PETROCHEMICAL PLANTS, Volume 1, 3rd Edition

Mechanical Separations 269
a-ix
Scrubbers Cleon

Scrubber separators use a liquid to form some type of
liquid surface (spray droplets, film, etc.) to assist the inter-
nal arrangements of the separator in the separating Cyclonic
action. Essentially the incoming dust or liquid particles Liquid in Scporotor
are wet by the action of the liquid (usually water or oil)
and are made larger and/or heavier and thus can be sep-
arated from the moving stream. There are many types and
styles of units falling in this classification (see Figures 458 Liquid out
to 464. Reference [36] provides a good summary of man- Figure 4-59. Venturi scrubber. Courtesy of Chemical Construction
ufacturers and their products for wet scrubbing. Corp.
One or more of the following mechanisms are
employed in the separating action of the wet scrubbers.

1. Impingement-on internal parts.
2. Wetting-of particle to help agglomerate and pre-
vent re-entrainment.
3. Diffusion-dust particles deposited on the liquid
droplets. Predominant for the submicron and parti-
cles up to about 5p.

Clean Gas

Dirty Gas I
Inlet
Figure 4-58. Cyclonic scrubber. Courtesy of Chemical Construction Figure 4-60. Impingement scrubber. Courtesy of Peabody Engineer-
Corp. ing Corp.