Electrostatic response enhanced fiber filters: A long-term, low-resistance solution for particles removal in building ventilation systems

Abstract

Fibrous filters are commonly employed in building ventilation systems to capture airborne particles and maintain acceptable indoor air quality. Introducing electrostatic forces into fibrous filters is an effective strategy that enhances filtration efficiency while maintaining low air resistance by synergistically combining electrostatic and mechanical filtration, especially for coarse filters. In this study, polydopamine (PDA) was utilized to modify a specially structured three-dimensional (3D) woven filter, resulting in reusable, washable functional fibers with enhanced electrostatic properties for sustainable air filtration applications. By integrating functional fiber filters with a carbon-brush ionizer, an Electrostatic Response Enhanced (ERE) system was developed to enhance electrostatic interactions, thereby achieving high-efficiency particulate removal with minimal airflow resistance. The ERE system demonstrated a remarkable enhancement in performance, achieving twice the filtration efficiency of the unmodified filter while maintaining a low pressure drop of just 32 Pa at an air velocity of 2.0 m/s. According to the air filter classification standards, the ERE was upgraded to a medium-efficiency filter, representing an improvement of three levels compared to the original 3D filter. Furthermore, the ERE system demonstrated consistent filtration efficiency following cleaning for dust removal, highlighting its strong potential for practical and sustainable use in ventilation and air purification systems.