Development of an Electrostatic Precipitator With a Novel Dry-Cleaning Apparatus for Building Ventilation Systems

Electrostatic precipitators (ESPs) offer a durable solution for enhancing indoor air quality. However, traditional cleaning techniques often pose financial burdens and result in issues such as electrode degradation and particle re-entrainment, which is crucial for building management. In this study, we introduced an ESP with a novel dry-cleaning apparatus tailored for indoor air purification systems. The novel cleaning apparatus utilized a combination of compressed air-blasting and vacuum suction mechanisms to dislodge and extract particles from the collection plates. Moreover, the ESP incorporated a two-stage design featuring a charger equipped with carbon brush ionizers and a collector comprising carbon ink–coated plastic plates. This design not only mitigates ozone emissions but also reduces installation costs. Our results revealed a consistent cleaning efficiency exceeding 98% under optimal operational conditions, restoring reduced collection efficiency due to contamination. Finally, we conducted field demonstration experiments in subway stations. We retrofitted an air handling unit with our ESP system and dry-cleaning apparatus, showing a collection efficiency of 99.4% for PM₁. To validate the efficacy of our dry-cleaning apparatus, we conducted a 16-day test at a vent outlet of a subway station. The field demonstration of the dry-cleaning apparatus showcased nearly flawless recovery of collection efficiency to the initial state. In summary, our investigation represents a significant advancement in overcoming the prevailing challenges associated with ESP utilization in indoor air purification applications.