The wet electrostatic precipitator operates based on the same fundamental principle as a dry electrostatic precipitator. Both systems use high-voltage corona discharge to electrically charge particles, which are then attracted to collection surfaces under the influence of an electric field.

While dry electrostatic precipitators are designed for low-moisture gas streams, WESP systems are specifically developed for handling high-humidity or saturated flue gases.

Operating Principle

A key difference between wet and dry electrostatic systems lies in the method of particle removal.

In dry systems, collected dust is typically removed using mechanical or acoustic cleaning. In contrast, WESP systems continuously wash the collection surfaces using water, preventing dust accumulation and ensuring stable long-term performance.

This wet cleaning process enables the efficient removal of fine particulate matter and condensable pollutants that are difficult to capture using conventional systems.

Application Capability

WESP systems are highly effective in removing a wide range of pollutants, including:

• Fine particulate matter (PM2.5)
• Acid mist such as SO₃
• Aerosols
• Heavy metals (Hg, As, Se, Pb, Cr)
• Organic pollutants such as PAHs and dioxins

After treatment, particulate emissions can be reduced to below 10 mg/m³, and in many cases even below 5 mg/m³.

Performance remains stable regardless of dust characteristics, making WESP particularly suitable for moist or saturated flue gas conditions.

System Advantages

• High purification efficiency with consistent performance
• Low pressure drop and reduced overall energy consumption
• No moving parts, minimizing maintenance and eliminating re-entrainment risks
• Suitable for high-temperature and high-pressure operating conditions
• Modular design allowing easy scaling for large-capacity systems
• High allowable operating temperature, typically up to 250 °C depending on configuration