Pulsed corona for removing volatile impurities from drinking water

Drinking water can be contaminated with hydrocarbons through industrial waste and also as consequence of disinfecting water with chlorine. Trihalomethenes (THMS) are found in drinking water and are believed to be carcinogens. Many of these compounds are soluble and can not be removed by common techniques. Air stripping by itself is used as means of reducing the amount of volatile substances in the water. The paper reports a combination of air stripping and pulsed corona to remove THMS from water. A specially designed pulsed generator was used where the rise time of the pulse is around 30 ns. Point to plane geometry, where nitrogen bubbles are introduced at the point was used. Voltage level, gap spacing, electrode position, water type and the frequency of applied voltage are the main parameters varied in this study. In addition to the existence of the bubbles, voltage level and water type are the controlling parameters of the water treatment process.