Water purification by ozone generator employing non-thermal plasma

Abstract

A plasma-based Ozone Generator has been constructed using non-thermal plasma technology and taking oxygen as a precursor. Ozone has generated by the electric discharge of molecular oxygen. Optimum conditions of ozone production were tested by varying applied voltage (1kV–16kV) and plasma discharge time (3–40min) keeping a constant flow rate of 2 l/min. The maximum obtained gaseous ozone concentration was 490 ppb in 15sec at a maximum applied voltage of 16 kV. Ozone has been treated with 0.00003 M indigo dye solution to measure dissolved ozone amount, analyzed by UV–Visible spectroscopy, and has calculated maximum dissolved ozone concentration of 51.74 ppm at 16 kV for a maximum time of 40min. Bandgap energy has also been analyzed for all ozone-treated indigo samples. Sewage, Canal, and Tap water have been treated with ozone for time 5min–60min at 16 kV. Water purification has been analyzed by UV–Visible spectroscopy, Optical microscopy, and digital TDS meter. After ozonation, total dissolved solids for sewage water have reduced from 462 ppm to 282 ppm. This value was reduced from 355 ppm to 212 ppm for tap water.