ESP handle complex, corrosive, and hazardous gases in chemical plants.

The following are the main challenges and corresponding solutions for the application of electrostatic precipitators in chemical plants:

Challenge 1: Complex Flue Gas Composition with Risks of Corrosion, Flammability, and Explosiveness

Problem Description: Chemical flue gas often contains acidic gases such as SOₓ, NOₓ, HCl, and HF. When the temperature falls below the dew point, these gases form highly corrosive acids that corrode the internal equipment. Additionally, the flue gas may contain combustible gases like hydrogen, carbon monoxide, methane, or combustible particles such as tar, which pose risks of combustion or even explosion under high-voltage electric fields.

Solutions:

1. Comprehensive Anti-Corrosion Design: Use materials such as stainless steel (e.g., 316L), fiberglass reinforced plastic (FRP), or special composite materials for internal components including the precipitator shell, collection electrodes, and discharge electrodes. Apply anti-corrosion linings (e.g., glass flake resin) for additional protection. Furthermore, implement high-standard insulation and tracing on the shell and hoppers to ensure the wall temperature always remains 20-30°C above the acid dew point, preventing condensation.

2. Intrinsic Safety and Explosion-Proof Design:

· Explosion-Proof Design: Install sufficient explosion vents/rupture discs on the precipitator and ducts, and employ an inert gas (e.g., nitrogen) purging system to reduce oxygen concentration inside the housing, eliminating explosive atmospheres.

· Safety Interlocking: Integrate closely with the production process, continuously monitoring the concentration of combustible gases and temperature. Immediately cut off the high-voltage power and activate emergency procedures if limits are exceeded.

Challenge 2: High Dust Adhesiveness, Prone to Hardening, Extreme Difficulty in Cleaning

Problem Description: Many chemical processes (e.g., resin, tar, pesticide intermediate production) generate extremely adhesive dust or mist droplets. These substances firmly adhere to the electrodes and are difficult to remove with conventional rapping. This can lead to "corona quenching" (where the discharge electrode is enveloped, preventing corona current generation), rendering the precipitator completely ineffective and causing blockages in the ash handling system.

Solutions:

1. Special Cleaning Methods:

· Moving Electrode Technology: In the final field, use moving collection plates combined with rotating brush cleaning. This can thoroughly remove adhesive dust and is one of the most effective technologies for handling highly sticky dust.

· Wet Electrostatic Precipitator (WESP): Utilize water film cleaning, where plates are washed by continuous or intermittent spraying. This fundamentally solves the adhesion problem and simultaneously allows for cooperative removal of acid mist and fine particulate matter.

2. Electrode Configuration Optimization: Employ discharge electrodes like spiral wires or spike wires that are less prone to adhesion, and use smooth collection electrode plates such as large C-type or Z-type plates to structurally reduce adhesion points.