Computational Fluid Dynamic Modelling of Particle Charging and Collection in a Wire-to-Plate Type Single-Stage Electrostatic Precipitator

Abstract

Electrostatic precipitators (ESPs) have been widely used to control particulate pollutants, which adversely affect human health. In this study, a computational fluid-dynamic model for turbulent flow, particle trajectory, and particle charging in ESPs is presented using a pre-developed corona discharge model (Kim et al., 2010), wherein electric field and space charge distributions in the plasma region are numerically calculated. The ESP under consideration is a wire-to-plate single-stage ESP, which consists of a series of discharge wires and two collecting plates. Two different kinds of particulates are considered in this study; fly ash and sucrose particles. Fly ash was selected because many ESPs have been utilized in coal-fired power plants to capture fly ash particles generated from combustion. Sucrose was selected to compare our numerical calculation results with experimental data found in literature. The electrical characteristics of the ESP, particle trajectories, particle charge numbers, and collection efficiencies under various operating conditions are demonstrated. For fly ash, the overall collection efficiencies based on particle mass are 61, 86, 95, and 99% at 45, 50, 55, and 60 kV, respectively, at a flow velocity of 1 m s–1.