EFFECT OF THE FORM OF ELECTRIC DISCHARGE ON PHYSICOCHEMICAL PROPERTIES OF PLASMA-ACTIVATED DISTILLED AND GROUND WATERS

Abstract

A comparative study of some physicochemical properties of aqueous solutions resulted from the treatment of distilled and ground waters by pulsed discharges has been performed. Changes in the pH value, the conductivity of the solution, and the content of NO3¯ anions and Ca++, Mg++, K+, and Na+ cations were studied. Water bodies were affected by active particles formed in the air under the action of a pulsed discharge, which is implemented in two options. The first option is conventionally called ‘bubble discharge’ since it assumes the ignition of a discharge in an air bubble in direct contact with a liquid. The second option is the case when active particles, which are formed in an air stream under the action of a barrier discharge, are blown into a liquid. It is shown that the bubble discharge in ground water gives the maximum performance for the NO3¯ anions, while in the case of barrier discharge the best performance in the formation of NO3¯ anions is observed in distilled water. The pH value for ground water increases from 8.1 to 8.6 in the course of a 10-minute treatment using both discharges. However, in the case of distilled water treatment an inverse relationship is observed, so its value decreases from 7.5 to 3.5 pH. A multiple increase in the content of Ca++ and Mg++ cations in the water sample is observed when groundwater treating. Presumably, their increase in solution is associated with the transition of insoluble salts of calcium and magnesium carbonates (constant water hardness) into water-soluble nitrates (temporary hardness). In addition to magnesium and calcium ions, potassium and sodium cations were monitored in water samples. Their concentration in water was insignificantly affected by the treatments with discharges.