| A widely used oxidant for water disinfection is hypochlorous acid, the oxidant produced by reacting chlorine gas, calcium hypochlorite, or sodium hypochlorite with water. These chemicals are potentially hazardous causing fires, explosions, and/or death when improperly handled. As an alternative to present disinfection practices, a method for the on site generation of an oxidant in recirculating, low salt content fluids was considered. In this process, a fluid was pumped from a holding tank through a surge tank (used to smooth the flow); then it passed through an electrochemical reactor, was treated, and was returned to the holding tank. A randomly oriented, graphite fiber-polymer matrix composite was used as the electrode material for the treatment reactor, which was powered using an alternating current. It was desirable to use an AC system in order to prevent electrode fouling. When the polarity of the reactor was reversed causing the cathode to become an anode, the accumulated fouling products on the cathode were removed. Thus, the system was self-cleaning and did not require the periodic maintenance of a DC electrolysis system. The system used NaBr and NaCl as a source for halogen ions. The halogens were oxidized at the anode and produced the respective hypohalous acid. Utilizing this process, it would not be necessary to handle or store the potentially dangerous chemicals presently used.; This research program characterized the operation and performance of the University of Virginia AC electrochemical disinfection system in treating latex emulsions and swimming pool waters. The information obtained provides a better understanding of this reactor system and will facilitate the application of this technology to other systems. |
