Effect of collection efficiency and reducing ozone generation in an electrostatic precipitator with knife edge disk type electrode

In this study, the experiments were carried out to investigate the effect of a wire diameter on reducing ozone generation and improving the collection efficiency for particle sizes larger than 24 nm in an electrostatic precipitator (ESP) with wire electrode. Furthermore, the effect of the ESP with a knife-edge disk electrode was also investigated, since a wire will be broken. The ESP consisted of a discharging section and an electrostatic section. Two types of discharging sections were used. One was wire-to-plate configuration, and another was a knife-edge disk electrode structure. Positive DC high voltage was applied to the ESP, and gas velocity was 0.6 m/s. As a result, the collection efficiency increased as the diameter of the wire electrode decreased. The efficiency for particle sizes greater than 400 nm achieved more than 99.3%, and the average efficiency for the particle sizes between 24 nm and 213 nm was 99.8% at the ozone concentration of 0.01 ppm and the fine wire diameter of 0.1 mm. In the ESP with knife edge disk type electrode, the efficiency increased with decreasing the diameter of the disk electrode. The collection efficiency for particle sizes larger than 400 nm achieved 99.8% or higher, and the average efficiency for the sizes between 24 nm and 213 nm was 99.0% at the ozone concentration of 0.01 ppm and the disk diameter of 28 mm. The effect which was equivalent to the ESP with fine wire electrode was obtained in the ESP with knife edge disk electrode.