Plasma assisted water treatment using an atmospheric air plasma applicator

Abstract

Plasma assisted water treatment systems present a compelling pathway for modification of water chemistry with reduced dependence on chemicals. Plasma production of oxidizing and reducing agents for chemical abatement, contaminant removal, and production of aqueous chemical agents without chemical feedstock present a potential transformative technology in the area of water treatment.An atmospheric plasma source operating at 162MHz1 is used to form reactive species that are incident on a downstream water source. While studying a variety of water treatment applications, several key challenges for practical implementation of this technology have been identified including improved pathways for water/plasma interaction and optimized chemistry for specific water treatment applications. Design of an improved device with increased efficiency in both airflow and water exposure will be presented. The interaction between the primary plasma discharge and water source, with emphasis on chemical composition and potential pathways for chemistry control are highlighted. Of specific interest is production and characterization of hydroxyl radicals through plasma water interaction. Experiments that characterize plasma conditions (specifically chemistry) andchanges to water chemistry will be presented. Potential applications of interest in the area of water treatment including treatment of perfluorinated compounds, atrazine, and dioxane in water supplies will be presented.