Particles' re-entrainment in electrostatic precipitators

Abstract

This paper is aimed at investigating the re-entrainment phenomena of particles in wire-duct electrostatic precipitators. This calls for assessment of the forces acting on a particle positioned in the precipitator nearby the collecting plate. These include Van Der Waals, Johnsen Rahbek and repulsion forces. Re-entrainment takes place when the repulsion force exceeds the resultant of both the Van Der Waal and Johnsen Rahbek forces. To estimate the repulsion force, the electric field acting on the particle is required as calculated by using the charge simulation method. Conducting and dielectric particles are investigated. Re-entrainment takes place for dielectric particles at particle radius greater than 1 μm in agreement with previous findings. The particle radius values at re-entrainment are smaller than those for metal ones.