Improvement of Surfactant Decomposition by Superposition of Pulsed Discharge on the Water and Ozone Injection
S. Kanazawa, S. Geng, T. Okawa, S. Akamine, and R. Ichiki
Department of Electrical and Electronic Engineering, Oita University, Japan
Abstract- In this study, we proposed a novel method to produce OH radicals for the treatment of water including persistent compounds by superposition of pulsed discharge on the water and ozone injection. As a test liquid, an aqueous solution including a surfactant was used to evaluate the water treatment efficiency. Taking into account the nature of the surfactant, the surface discharge mode was adopted. A hollow metal needle was used as the stressed electrode, and the tip of the electrode was set 1mm above the water surface. While a ring electrode was submerged in water as the grounded electrode. A pulsed streamer discharge was generated on the water surface. Moreover, the ozone injection through the needle electrode was performed to investigate the synergistic effect. The results indicated that linear alkylbenzene sulfonate (LAS) was decomposed effectively by using the proposed method. The deformation of the water surface underneath the needle electrode was observed by the gas injection, resulting in the penetration of the streamer into the water. Also the electrohydrodynamic (EHD) flow, induced in water solution, enhances the mixing of the solution.
Keywords-Pulsed discharge on the water surface, ozone, OH radical, LAS, EHD-induced liquid flow, synergistic effect