PP Spray Tower

A PP spray tower(polypropylene spray tower)is a highly corrosion-resistant,wet-scrubbing air pollution control device used to treat acidic,alkaline,and particulate-laden industrial exhaust gases.It is widely adopted in chemical,electroplating,metallurgical,pharmaceutical,and semiconductor industries due to its excellent chemical stability,low cost,and easy maintenance.

1.Construction&Components

Tower Body:Made of PP(polypropylene),resistant to acids,alkalis,and most organic solvents;operates reliably at temperatures≤60°C.

Spraying System:Multi-layered PP nozzles and circulation pipes that atomize scrubbing liquid into fine droplets for maximum gas–liquid contact.

Packing Layer:Filled with polyhedral hollow balls,Raschig rings,or Pall rings to increase contact area and prolong reaction time.

Mist Eliminator:Installed at the top to remove entrained water droplets and prevent secondary pollution.

Circulation Water Tank&Pump:Stores and recirculates scrubbing liquid(water or chemical solutions like NaOH/H₂SO₄).

Optional:Chemical dosing system,liquid level gauge,pH controller,and inspection ports.

2.Working Principle

Gas Inlet:Contaminated gas enters the tower from the bottom and flows upward.

Counter-current Contact:Scrubbing liquid is sprayed downward from the top,forming a fine mist.Upward gas and downward liquid interact counter-currently.

Pollutant Removal:

Acidic gases(HCl,SO₂,HF):React with alkaline scrubbing liquid(e.g.,NaOH)to form soluble salts.

Alkaline gases(NH₃):Absorbed by acidic solutions.

Dust/mists:Captured by liquid droplets via impingement and adsorption.

Demisting&Discharge:Clean gas passes through the mist eliminator to remove water droplets,then exits at the top.

Liquid Recirculation:Contaminated liquid flows back to the tank for circulation or periodic treatment.

3.Key Advantages

Superior Corrosion Resistance:PP material withstands pH 1–14,ideal for strong acid/alkali fumes.

High Purification Efficiency:Removes 90%+of acid mist,dust,and soluble VOCs.

Cost-Effective:Lower material and maintenance costs compared to stainless steel or FRP towers.

Lightweight&Durable:Easy to install;service life of 5–10 years under normal conditions.

Stable Operation:Simple structure,low pressure drop,and compatibility with automated control.

4.Typical Applications

Acid Mist Treatment:Electroplating,pickling,and metal finishing(HCl,H₂SO₄,NOₓ).

Alkaline Waste Gas:Ammonia(NH₃)from fertilizer,livestock,or chemical plants.

Dust&VOC Control:Paint spray booths,printing,and pharmaceutical manufacturing.

Other Scenarios:Flue gas desulfurization(FGD),hydrogen fluoride(HF)removal,and odor control.

5.Technical Specifications(General)

Material:Polypropylene(PP)

Temperature Range:-10°C to 60°C

pH Tolerance:1–14

Efficiency:90%–90%for acid/alkali gases

Pressure Drop:200–500 Pa

Custom Sizes:Diameter 500–3000 mm;Height 2000–8000 mm