Quantifying the Effect of Nonwoven Conductive Fabric Liners on Electrostatic Precipitator Submicrometer Particle Removal Efficiency

Electrostatic precipitators (ESP) are widely used for fine particle control. The collection surface is sometimes coated with materials to enhance pollutant removal. The use of nonwoven fabric liner inserts for submicrometer particle removal in an ESP was investigated. Two of the nonwoven fabrics (HAS-10(S)F1SS/PML and HPS-10(S)FIL/F1SS/BSL) were conductive, whereas the third one (RR-10(S)F1SS/DSL) was non-conductive. The current-voltage characteristics of the ESP revealed lower inception voltages when conductive fabrics were used (5.0 kV for HAS-10(S)F1SS/PML and 6.1 kV for HPS- 10(S)FIL/F1SS/BSL) than when no fabric was used (6.9 kV), whereas no distinct inception voltage was observed with the non-conductive fabric due to it possessing lower concentrations of reactive electrons and ions on the surface compared to the conductive fabrics. The particle capture performance of the ESP with and without nonwoven fabrics was studied using NaCl particles at applied voltages ranging from 0 kV to 7.5 kV. Due to their lower inception voltages and higher ion concentrations, the conductive fabrics exhibited higher particle removal efficiencies than the other test cases when the applied voltages were lower than 7.5 kV. High removal efficiencies were still obtained at an applied voltage of 7.5 kV except when the particles were smaller than 30 nm or larger than 700 nm due to the lower charging efficiency with ultrafine particles and the re-entrainment of larger particles into the gas stream. However, the use of either conductive or non-conductive fabric resulted in a higher charging efficiency with ultrafine particles and the reduced re-entrainment of large particles. Our findings elucidate the enhancement of submicrometer particle control in ESPs when using conductive fabrics.