The vertical liquid spray tower is a type of wet scrubber used for gas cleaning, especially in air pollution control systems. It removes particulate matter, acid gases, or volatile pollutants from industrial exhaust streams by spraying liquid (usually water or a chemical solution) vertically down (or sometimes up) through a packed or open column where it contacts the rising gas stream.

Basic Structure and Operation

1. Vertical Tower Body: A cylindrical or rectangular chamber, usually made of corrosion-resistant materials (like PP, PVC, or FRP).

2. Spray Nozzles: Located near the top, spraying fine droplets of liquid downward.

3. Gas Inlet: Typically located near the bottom side, allowing gas to flow upward (counter-current flow).

4. Mist Eliminator / Demister: Installed at the top to remove entrained droplets before clean gas exits.

5. Liquid Collection / Re-circulation Tank: At the bottom to collect sprayed liquid, often reused after treatment.

⚙️ Working Principle

• Contaminated gas enters from the bottom.

• Scrubbing liquid is sprayed from the top via nozzles.

• As gas moves upward and liquid moves downward (counter-current), pollutants are absorbed or neutralized.

• The cleaned gas exits from the top, while the polluted liquid is collected at the bottom for treatment or recycling.

Common Applications

• SOx, NOx, HCl removal from flue gas

• Ammonia, chlorine, formaldehyde, VOC control

• Dust removal

• Odor control in wastewater and chemical industries

✅ Advantages

• Simple design and operation

• Effective for soluble gases and particulates

• Can handle high-temperature gas

• Low pressure drop if packed bed is not used

⚠️ Considerations

• Requires continuous water or chemical supply

• Produces wastewater that needs treatment

• Spray nozzle maintenance is important to avoid clogging