An investigation of an underwater steam plasma discharge as alternative to air plasmas for water purification

Abstract

An underwater steam plasma discharge, in which water itself is the ionizing media, is investigated as a means to introduce advanced oxidation species into contaminated water for the purpose of water purification. The steam discharge avoids the acidification observed with air discharges and also avoids the need for a feed gas, simplifying the system. Steam discharge operation did not result in a pH changes in the processing of water or simulated wastewater, with the actual pH remaining roughly constant during processing. Simulated wastewater has been shown to continue to decompose significantly after steam treatment, suggesting the presence of long-lived plasma produced radicals. During steam discharge operation, nitrate production is limited, and nitrite production was found to be below the detection threshold of (roughly 0.2 mg L −1 ). The discharge was operated over a broad range of deposited power levels, ranging from approximately 30 W to 300 W. Hydrogen peroxide production was found to scale with increasing power. Additionally, the hydrogen peroxide production efficiency of the discharge was found to be higher than many of the rates reported in the literature to date.

In‐Liquid Plasma Synthesis of Nanographene with a Mixture of Methanol and 1‐Butanol

“…In‐liquid plasma technologies can be categorized into two types, based on the electrode configuration. In the first type, both electrodes are submerged in the liquid . Submerged electrode type discharge requires bubble generation for plasma ignition.…”

“…Submerged electrode type discharge requires bubble generation for plasma ignition. The bubbles are generally generated by joule heating or ultrasonication . Kang et al.…”

“…Plasma generated in the liquid phase, i. e., in-liquid plasma, has great potential for a wide range of applications, such as water purification [1][2][3][4][5] and material synthesis. [6][7][8][9][10][11][12][13][14][15][16][17][18][19] Low-cost, high-quality materials have increasingly become more important for solving environmental concerns with clean water, energy production, [20][21][22][23][24] and so on.…”

“…[2][3][4][6][7][8][9][10][11][12] Submerged electrode type discharge requires bubble generation for plasma ignition. The bubbles are generally generated by joule heating [2,6,7] or ultrasonication. [13] Kang et al reported the synthesis of carbon nanospheres using a submerged type in-liquid plasma employing benzene.…”

Electrical and spectral characteristics of a tube-to-plate helium plasma generated using dielectric barrier discharge in water

“…In the past decades, dielectric barrier discharges (DBDs) have attracted growing attention in organic pollutants removal from water [1][2][3][4][5]. It is demonstrated that electrical discharges of DBD applied in water could directly or indirectly cause organic compound degradation by © 2016.…”