Dielectric Barrier Discharge based Mercury-free plasma UV-lamp for efficient water disinfection

Abstract

A structurally simple dielectric barrier discharge based mercury-free plasma UV-light source has been developed for efficient water disinfection. The source comprises of a dielectric barrier discharge arrangement between two co-axial quartz tubes with an optimized gas gap. The outer electrode is an aluminium baked foil tape arranged in a helical form with optimized pitch, while the inner electrode is a hollow aluminium metallic rod, hermetically sealed. Strong bands peaking at wavelengths 172 nm and 253 nm, along with a weak band peaking at wavelength 265 nm have been simultaneously observed due to plasma radiation from the admixture of xenon and iodine gases. The developed UV source has been used for bacterial deactivation studies using an experimental setup that is an equivalent of the conventional house-hold water purifier system. Deactivation studies for five types of bacteria, i.e., E. coli, Shigella boydii, Vibrio, Coliforms and Fecal coliform have been demonstrated with 4 log reductions in less than ten seconds.

Towards high throughput plasma based water purifiers: design considerations and the pathway towards practical application

“…In this respect, the packed bed reactor's geometry inherently takes advantage of UV photons produced. Microdischarges have been investigated as intense UV light sources for water purification and offer efficient mercury-free operation [90]. In principle, it is possible to assess the UV dose via absolute emission spectr oscopy or the use of a chemical probe such as potassium iodide [91].…”

Testing of Sr-Doped ZnO/CNT Photocatalysts for Hydrogen Evolution from Water Splitting under Atmospheric Dielectric Barrier Plasma Exposure

“…When inert gases are used to make a discharge, the DBD reactor also makes diatomic molecules. These radiations interact with solids, gases, and liquids in different ways . In this study, argon was used as plasma gas.…”

Disinfection-Dechlorination Battery for Safe Water Production

“…In chemical disinfection, chemical substances are added to seawater to produce total residual oxidants (TROs) known as disinfection agents (e.g., chlorine, hypochlorite, and ozone). In electrochemical disinfection, total chlorine-based disinfection species (TC) are produced in NaCl-containing solutions in situ because of the application of an electric current at the interphase of the electrode and water. , Among various disinfecting methods, − the electrochemical on-site production of chlorine , (Figure b) is widely used because of its cost-effectiveness and simplicity in particular for seawater disinfection. This process produces chlorine by adjusting the applied potential or current in the system.…”