Simultaneous Removal of Fine Particles and VOCs by a Two-Stage Electrostatic Precipitator Based on Sawtooth-Rod Electrode Discharge Charging
A two-stage electrostatic precipitator (ESP) integrating a sawtooth-rod electrode precharging unit and a plate-plate collection unit was developed for simultaneous removal of fine particles and volatile organic compounds (VOCs) from catering fumes. Using KCl particles and toluene as surrogates, the system achieved a fine particle (<0.3 µm) collection efficiency of 91% and a total particle collection efficiency exceeding 98% at applied voltages of +12 kV (sawtooth-rod) and -8.5 kV (plate-plate), with an ozone concentration of 176.9 mg/m³. The presence of particles enhanced toluene degradation, increasing removal efficiency from 29.2% to 53.1%. Positive DC discharge on the sawtooth-rod electrode yielded a higher corona current (800 µA vs. 375 µA for negative) and lower ozone generation (101.4 mg/m³ vs. 176.9 mg/m³), indicating superior suitability for catering fume treatment. The stable discharge characteristics of the sawtooth-rod electrode reduce energy consumption and extend operational cycles, offering a promising technical pathway for efficient, compact, and intelligent ESP systems in catering fume purification.