FRP spray tower

The FRP spray tower (also known as the acid mist purification tower) is a wet-type waste gas treatment device with a fiberglass reinforced plastic (FRP) shell. It combines corrosion resistance, lightweight, high strength, and low cost. Its core function is to remove acidic or alkaline soluble pollutants from waste gas through a combination of gas-liquid countercurrent contact, mass transfer through filler, and chemical/physical absorption.

Working Principle (Four-Step Process)
Phase Process Description Mechanism
1. Waste Gas Intake: Polluted waste gas is introduced into the tower from the bottom by a fan and evenly distributed through a gas distributor. This prevents flow deviation and improves absorption efficiency.
2. Mass Transfer Through Filler: Waste gas flows upward through the FRP filler layer (Pall rings/Raschig rings), where it countercurrently contacts the absorption liquid (alkaline solution, acid, or water) sprayed from top to bottom. Increases gas-liquid contact area and extends residence time.
3. Absorption Reaction: Pollutants such as HCl, HF, NH₃, H₂S, SO₂, and chromic acid mist in the exhaust gas are dissolved or neutralized by the scrubbing liquid, producing harmless salts. Chemical reaction: For example, HCl + NaOH → NaCl + H₂O.
4. Demisting and Emission: The purified gas passes through FRP baffles or wire mesh demisters to remove droplets before being discharged to standard standards by the overhead fan. Preventing "white smoke" secondary pollution

Applicable Gas Environments (Typical Scenarios)
Industry Processing Gas Characteristics
Chemical/Pharmaceuticals: HCl, HF, H₂S, NH₃, SO₂, HCN, etc. High concentrations, strong corrosion, high temperatures (≤80°C)
Electroplating/Pickling: Chromic acid mist, nitric acid mist, hydrogen cyanide. Contains heavy metal ions, strong oxidizing properties
Waste Incineration/Sewage Treatment Plants: Malodor (NH₃, H₂S), organic mercaptan, Complex composition, intermittent emissions
Electronics/Semiconductors: Silane, phosphine, NOₓ, Fluorine- and silicon-containing dust
Laboratory/Printing: Formaldehyde, phenols, VOCs, Large concentration fluctuations, low air volume

FRP Material Advantages
- Strong corrosion resistance: Withstands long-term immersion in 30% hydrochloric acid, 50% sulfuric acid, hydrofluoric acid, and alkaline solutions.
- Lightweight and High-Strength: Weighing only 1/4 the weight of steel, yet possessing strength close to that of steel, it is easy to install and transport.
- Excellent Insulation: Suitable for locations with electrical equipment, preventing static electricity buildup.
- Temperature Range: -30°C to +80°C (special resins can reach 120°C).

 Precautions
- For exhaust gases containing hydrofluoric acid, use vinyl ester resin FRP to prevent corrosion of the glass fiber.
- For high-temperature exhaust gases (>80°C), a precooler is required to prevent FRP degradation.
- Regular Maintenance: Check nozzle blockage, packing fouling, and demister dust accumulation every 3-6 months.

The FRP spray tower uses a combination of countercurrent spraying + packing mass transfer + chemical absorption to efficiently treat acid mist, alkaline mist, odor, and some VOCs. In corrosive working conditions such as the chemical industry, electroplating, sewage treatment plants, and laboratories, it combines high purification efficiency (90-98%) with low cost advantages. It is the preferred equipment for the treatment of small and medium air volumes and medium to high concentrations of acidic and alkaline waste gases.