Factors Influencing the Sterilization of E. coli in a High-Voltage Electric Field: Electric Field Strength, Temperature and Humidity

The application of a high-voltage electric field (HVEF) is crucial for mitigating the growth and reproduction of pathogenic microorganisms on solid surfaces. However, the electric field distribution of HVEF in the undischarged state and bactericidal effect remain largely unexplored. Herein, a unipolar wire–plate HVEF device was developed and its field strength distribution was simulated by COMOSL software (version 6.2). The simulation analysis revealed that the electric field strength and space charge density of HVEF in the undischarged state reached a maximum at the discharge electrode and a minimum at the middle of the two electrode wires. The electric field strength and the inhomogeneity of electric intensity distribution also decreased with the increase in electrode spacing. The sterilization effect of E. coli was positively correlated with voltage and treatment time, but negatively correlated with electrode spacing, which was consistent with the change in the field strength of the simulation results. When the voltage was −12.5 kv and electrode spacing 2.7 cm, the sterilization rate was 98.03% at 60 min. In addition, the increase in treatment temperature and relative humidity also affected the electric field distribution, thereby improving the bactericidal effect. Our results revealed that the electric field distribution was the main factor affecting the sterilization effect of HVEF, which provided theoretical support for the design of HVEF sterilization equipment and the optimization of sterilization performance