Underwater Arc Discharge Treatment Using a High-Voltage Arc-Robust Supply

Underwater arc discharge is one of the most effective water treatment methods because of the effects of intense shockwaves and high ultraviolet radiations. In this article, a high-voltage underwater arc discharge system is proposed to study the inactivation of Escherichia coli (E. coli) bacteria, which has an arc-robust feature. It consists of a high-voltage capacitor charger (HVCC) and a discharge circuit. The HVCC is developed by an LCCL resonant converter to reach a current supply scheme that is inherently protected and robust against arc discharge. The detailed mathematical analysis and the design optimization of the resonant converter are presented. The discharge circuit is developed by a two-step spark gap scheme using an ultrafast high-voltage trigger circuit, providing a reliable system operation independent of the water conductivity. The proposed underwater arc discharge system is applied to 500 mL of pollutant water to study the system's performance on the inactivation of E. coli bacteria. The proper microbiological tests are carried out, showing the effectiveness of the proposed underwater arc discharge system. The complete inactivation of E. coli bacteria is achieved in an extremely short treatment time. Moreover, the experimental results are presented, which validate the desired performance of the proposed underwater arc discharge system.

Automated summary

In this article, a high-voltage underwater arc discharge system is proposed for the inactivation of E. coli bacteria. The system consists of a high-voltage capacitor charger and a discharge circuit, which are designed to protect and ensure stable operation of the arc discharge. By using a two-step spark gap scheme and an ultrafast high-voltage trigger circuit, the system can operate independently of water conductivity. The experimental results validate the effectiveness of the proposed system in achieving complete inactivation of E. coli bacteria in a short treatment time.