ents with minimal impact on their generating costs. It can be retrofitted into the last fields of existing ESP. Electo-Catalytic Oxidatin Technology uses a proprietary gas discharge technology to convert NOx and SO2 to acid mists, and to oxidize elemental mercury. It also uses advances in wet ESP technology to remove acid mists and other fine particles without saturating flue gas. The Electro-Catalytic Oxidation system consists of three sections: gas converter, condensing wet ESP, and acid recovery (ZET, 1999).The Gas Converter is used for the electrical oxidation of NOx, SO2 and Hg. As the flue gas enters the Gas Converter, it is exposed to a high voltage discharge which creates ionized species to oxidize pollutants. The oxidized pollutants then form the following particulates:•NOx gas forms nitric acid (HNO3) aerosol mist •SO2 gas forms sulfuric acid (H2SO4) aerosol mist•Elemental mercury vapor forms mercuric oxide (HgO) particulate Chemical reactions are initiated by collisions of high energy electrons with water and oxygen molecules present in the flue gas stream. This leads to the formation of oxygen and OH radicals.The oxygen and OH radicals then act to oxidize particulates that are present in the gas stream, particularly NOx, SO2, and Hg. Reactions subsequent to oxidation which produce acids take place in the discharge reactor or after the gas exits the reactor. All of the reactions can be made to occur at low temperature (150-300̊F). The second part of the Electro-Catalytic Oxidation system is the Condensing Wet ESP. The Condensing Wet ESP is used for acid aerosol and fine particulate collection. Wet electrostatic precipitators have been used successfully in industrial applications to collect acid mists for over 50 years, particularly in metallurgical plants and in sulfuric acid manufacturing. Wet ESPs have also shown to be very efficient collectors of PM2.5 and hazardous air pollutants, such as Hg...
