CaviPlasma: parametric study of discharge parameters of high-throughput water plasma treatment technology in glow-like discharge regime

Abstract

Abstract AC discharge in a dense hydrodynamic cavitation cloud in water, called CaviPlasma, has been studied at different discharge parameters. CaviPlasma stands for cavitation and plasma, which are two coupled basic phenomena of the novel technology enabling very high throughput of plasma water processing compared to other current technologies. In this article, the diagnostics and the properties of CaviPlasma discharge are discussed based on optical and electric characterization of the discharge phenomena together with the physico-chemical characterization of the plasma-treated water. The so-called unbridged mode of CaviPlasma operation is described, where the discharge propagates from a metal electrode towards a liquid electrode at the collapsing end of the cavitation cloud. The production of H, O and OH species in the discharge was proven by optical emission spectroscopy. The formation of hydrogen peroxide (H2O2) in water was determined by chemical methods. The energy yield for H2O2 generation is as high as 9.6 g kWh−1 and the generation rate is up to 2.4 g h−1. The degradation of phenol admixture in water was also studied. The article covers a parametric study enabling the development of tailored applications.