ESDC Series Wet Electrostatic Precipitator

The ESDC Series Wet Electrostatic Precipitator (WESP) is an advanced industrial air pollution control system designed for the efficient removal of fine particulate matter, acid mist, aerosols, ultra-fine droplets and other contaminants from process exhaust gas.

Unlike conventional dry electrostatic precipitators that rely on mechanical rapping to remove deposited dust, the ESDC Series uses a continuous water washing system. Water is sprayed onto the collecting electrodes to form a stable water film, which continuously washes captured contaminants from the electrode surface and carries them into the collection and drainage system.

Product Overview

The ESDC Series Wet Electrostatic Precipitator directly introduces water mist into the discharge electrode and corona discharge zones. When the fine droplets enter the strong electric field generated around the discharge electrodes, they become electrically charged and are further dispersed into finer droplets.

Inside the electrostatic field, several mechanisms work together, including electrostatic attraction, charged-droplet collision, interception, adsorption and agglomeration. These combined effects significantly enhance the capture of fine dust particles and aerosols.

Under the action of the electric field, charged particles migrate toward the collecting electrodes and are deposited on their surfaces. Continuous water spraying forms a uniform water film over the collecting electrodes. The flowing water washes away the collected contaminants and transports them to the lower collection section for drainage or further treatment.

Because the electrode surfaces are continuously washed, the system helps prevent dust accumulation, secondary dust re-entrainment and back corona. It is particularly suitable for applications requiring efficient control of fine and submicron particulate matter.

Working Principle

Dust-containing exhaust gas enters the ESDC Wet Electrostatic Precipitator through the inlet duct and flows into the high-voltage electrostatic field formed between the discharge electrodes and the grounded collecting electrodes.

A high-voltage DC power supply is applied to the discharge electrodes, generating corona discharge and ionizing the surrounding gas. The resulting ions collide with dust particles, fine droplets, aerosols and other contaminants in the exhaust stream, causing these particles to become electrically charged.

Once charged, the particles migrate toward the collecting electrodes under the force of the electrostatic field. When they reach the collecting surface, they are captured and retained on the electrode.

At the same time, the washing system continuously sprays water onto the collecting electrodes. A stable water film is formed along the electrode surface, continuously removing deposited dust and contaminants. The washing liquid then flows downward into the collection section and is discharged from the equipment.

The high-humidity environment inside the wet electrostatic precipitator also produces a large number of charged fine droplets. These droplets increase the probability of collision and charging of submicron particles, further improving the removal efficiency for fine particulate matter and aerosols.

After electrostatic collection and washing, the purified gas passes through the upper section of the equipment and is discharged through the exhaust outlet or transferred to subsequent exhaust gas treatment equipment when required.

Treatment Process

1. Exhaust Gas Intake: Polluted exhaust gas enters the wet electrostatic precipitator through the inlet duct.
2. Corona Discharge: The high-voltage DC power supply generates a strong corona field around the discharge electrodes.
3. Gas Ionization: Gas molecules inside the electric field are ionized and produce charged ions.
4. Particle Charging: Dust, mist and aerosol particles collide with the charged ions and become electrically charged.
5. Electrostatic Collection: Charged particles migrate toward the collecting electrodes under the action of the electric field.
6. Water Film Washing: The spray system continuously washes the collecting electrodes and removes accumulated contaminants.
7. Contaminant Discharge: Captured particles are transported downward with the washing water into the collection and drainage system.
8. Clean Gas Discharge: Purified exhaust gas leaves the equipment through the upper outlet.

Key Removal Capabilities

The wet electrostatic precipitation process is especially effective for contaminants that can be difficult to remove using conventional dry dust collection systems.

• Fine particulate matter
• Submicron particles
• Acid mist
• SO₃ acid aerosols
• Ultra-fine liquid droplets
• Sticky particulate matter
• High-resistivity dust
• Fine smoke and fumes
• Selected heavy-metal-containing particulate matter
• Mercury-containing particulate or aerosol contaminants under suitable process conditions

Product Features

• High Corona Power: The wet operating environment allows the system to provide strong corona discharge conditions, making it suitable for fine particles and SO₃ acid aerosols.
• High Fine-Particle Collection Efficiency: Electrostatic attraction combined with charged water droplets improves the capture probability of fine and submicron particles.
• Suitable for Sticky Dust: Continuous water washing helps prevent sticky contaminants from accumulating on the collecting electrodes.
• Suitable for High-Resistivity Dust: Wet electrostatic precipitation is less affected by dust electrical resistivity than conventional dry electrostatic precipitation.
• No Secondary Dust Re-Entrainment: Contaminants are washed away by water rather than removed through mechanical rapping, reducing the possibility of secondary dust generation.
• Reduced Back Corona: Continuous electrode washing keeps the collecting surfaces clean and helps minimize back-corona phenomena.
• Continuous Electrode Cleaning: The spray system maintains a water film on the collecting electrodes, allowing stable and continuous cleaning during operation.
• Suitable for High-Humidity Exhaust: The wet operating environment makes the equipment particularly suitable for humid exhaust streams.
• Low Final Dust Concentration: The technology is suitable for applications requiring very low particulate emission concentrations.
• No Mechanical Rapping System: The absence of a conventional rapping mechanism reduces the number of moving components inside the equipment.
• High Operational Reliability: Optimized electrode and spraying system design supports stable long-term operation.
• Reduced Maintenance Requirements: Continuous water cleaning helps reduce manual electrode cleaning and routine maintenance workload.
• Compact Equipment Structure: The equipment requires relatively little installation space and can be arranged in compact exhaust treatment systems.
• Flexible System Integration: The WESP can be integrated with scrubbers, desulfurization systems and other industrial exhaust gas treatment equipment.

Main Components

Advantages Compared with Dry Electrostatic Precipitators

Application Range

The ESDC Series Wet Electrostatic Precipitator is widely used for industrial dust, smoke, aerosol and fine particulate control in industries requiring high-efficiency exhaust gas purification.

• Iron and steel industry
• Building materials industry
• Power generation
• Chemical industry
• Carbon black production
• Metallurgical industry
• Non-ferrous metal processing
• Industrial furnaces
• Fine particulate emission control
• Acid mist treatment
• High-humidity exhaust gas treatment
• Industrial material recovery processes

Typical Treatment Configuration

Depending on the exhaust gas composition and emission requirements, the ESDC Wet Electrostatic Precipitator can be used independently or integrated with other air pollution control equipment.

Industrial Exhaust Gas → Pretreatment / Scrubber → ESDC Wet Electrostatic Precipitator → Exhaust Fan → Stack Discharge

For complex industrial exhaust gas, the equipment can also be integrated into multi-stage treatment systems according to dust concentration, temperature, humidity, pollutant composition and final emission requirements.

Why Choose the ESDC Series Wet Electrostatic Precipitator?

The ESDC Series Wet Electrostatic Precipitator combines high-voltage electrostatic collection with continuous water washing, providing an effective solution for the removal of fine dust, aerosols and mist from industrial exhaust streams. Compared with conventional dry electrostatic precipitation, the wet process helps eliminate secondary dust re-entrainment and reduces the influence of dust resistivity on collection performance.

Its compact structure, continuous electrode cleaning, low maintenance requirements and strong fine-particle removal capability make it particularly suitable for industrial applications requiring efficient final-stage particulate control.

The system can be customized according to exhaust gas volume, inlet dust concentration, particle characteristics, temperature, humidity, installation conditions and required emission performance.