From Dust Collectors to Multifunctional Platforms: A Review on Electrostatic Precipitators for Synergistic Multipollutant Control

Abstract

Electrostatic precipitators (ESPs), which are widely utilized in coal- and biomass-fired power plants, are transitioning from mere dust collectors to sophisticated flue gas treatment systems addressing SO2, NOx, VOCs, and Hg0. However, the energy penalties and catalyst lifetimes that influence industrial viability remain unquantified across various pathways. This review establishes a quantitative performance and energy-efficiency hierarchy for four enabling mechanisms: electrostatic adsorption, plasma-induced oxidation, ozone-assisted reactions, and catalytic coupling. Dry ESPs with alkaline sorbent injection can achieve over 90% SO2 removal at minimal energy costs; however, direct plasma oxidation of NO and Hg0 remains below 30% conversion unless specific energy densities reach between 200 and 1000 J/L─a 10- to 50-fold increase compared to conventional ESP operations. Hybrid plasma-catalytic systems enhance NOx removal to 80–95% and Hg0 oxidation to 90–99%, yet they are currently hindered by catalyst deactivation lifetimes that rarely exceed 500 h, while practical applications demand over 8000 h. We identify a critical trade-off between ozone efficiency and the lack of pilot validation exceeding 1000 h as central translational bottlenecks. By synthesizing a fuel-property-dependent analysis, we propose a roadmap that integrates electric-field-responsive catalyst design, smart ozone dosing, and standardized energy/performance metrics. This work provides a data-driven foundation for the power generation sector to evaluate the potential of retrofitting ESPs into compact, energy-efficient multipollutant control systems, thereby reducing the net auxiliary power load of air pollution control devices.