This document discusses different types of wet collectors used to remove particles from gas streams. It describes impingement scrubbers, which use horizontal plates with small holes to accelerate gas and atomize water droplets to impact particles. Spray towers are also discussed, which use spray nozzles to generate water droplets to impact particles as the gas moves upwards. The advantages and disadvantages of each type are provided, such as impingement scrubbers handling flammable dusts but creating waste disposal problems, while spray towers have lower pressure drops but mass transfer efficiencies.

1. WET COLLECTORS
GROUP MEMBERS:
MUHAMMAD BIN KAMARUDDIN (17DAS14F1039)
SITI NUR IDAYU BT. MOHAMMAD GHAZALI (17DAS14F1037)
FATIN SHAHIRA NABILA BT. SHAHROM (17DAS14F1041)

2. IMPINGEMENT SCRUBBER
 These scrubbers usually have one to three horizontal plates, each of which has a large
number of small holes.
 The gas stream accelerating through the holes atomizes some droplets in the water layer
above the plate.
 Particles impacts into these water droplets.

4. Advantages & Disadvantages of
impingement scrubbers
Advantages
• Can handle flammable and explosive dusts
with little risk.
• Provide gas absorptions and dust collection in
single unit.
• Can handle mists.
• Provides cooling for hot gases.
Disadvantages
• Effluent liquid can create water pollution
problem.
• Waste product collected wet.
• High potential for corrosion problem.
• Disposal of waste sludge may be very
expensive.

5. Spray tower
• This is the simplest type of particulate wet scrubber in commercial
service
• Sets of spray nozzles located near the top of the scrubber vessel
generate water droplets that impact with particles in the gas stream
as the gas stream moves upwards.

6. Function:
• Removal of air pollutants by inertial or
diffusional impaction, reaction with a
sorbent or reagent slurry, or absorption
into liquid solvent

8. Advantages & Disadvantages of
spray tower
Advantages
• Relatively low pressure drop.
• Relatively low capital cost.
• Relatively free from plugging
• Relatively small space requirement.
Disadvantages
• May create water (or liquid) disposal
problem.
• Waste product collected wet.
• Relatively low mass-transfer efficiencies.
• Relatively high operating costs.