Investigation of a pulse circuit design and pulse condition for the high energy efficiency on water treatment using pulsed power discharge in a water droplet spray

One of industrial applications by pulsed power technologies is water treatment using pulsed streamer discharge. The pulsed streamer discharge can generate ozone, chemical active species, ultraviolet rays and Shockwaves. All of these can be utilized to decompose the organic compounds in water. In the water treatment by discharge, energy efficiency for the treatment is very important factor at commercial viability. Therefore, we have been studying the decomposition of organic compounds in water using the pulsed streamer discharge in air with water droplet s for a high energy efficiency water treatment method. In this study, we have investigated a pulse circuit design and pulse conditions in which the energy is transferred effectively from the power supply to the discharge. The experimental set up consist of a pulsed power generator and a discharge reactor. A pulsed high voltage is generated by the pulsed power generator. The pulsed power generator is consist of high voltage FET switches, resistors and capacitors. In this pulsed power generator, the output energy from the capacitors is limited by a switching time of the high voltage FET switch. The discharge reactor has a coaxial electrode that consists of a stainless steel wire of 0.28mm diameter for applying pulsed voltage and a cylindrical stainless steel mesh of 38mm inner diameter for a ground electrode. The electrode length of the streamer discharge area is 300mm. In an experiment, an optimum pulse width for high energy efficiency was investigated.