The combined removal of sulfur dioxide (SO{sub}2, up to 3000 ppm) and nitrogen oxides (NO and NO{sub}2, up to 1200 ppm) has been investigated in a bench-scale pulsed-corona enhanced wet electrostatic precipitator (wESP) with the optional injection of ammonia and/or ozone. The reaction of ammonia with SO{sub}2 produces submicron aerosols under certain conditions. Experiments have shown the feasibility of combined SO{sub}2 and NO{sub}x removal from simulated flue gases by the action of these in-situ generated aerosols. The mechanisms for NO{sub}x removal include oxidation of NO to NO{sub}2 and subsequent absorption of NO{sub}2 into the water wall of the wESP. The results have shown that injecting NH{sub}3 (NH{sub}3/NO{sub}x molar ratio 1) resulted in NO{sub}x removal of ～13 in a simulated combustion flue gas. Injecting 200 ppm ozone (no ammonia) increased NO conversion to 35 by oxidation, but total NO{sub}x removal increased to only 17. Without the formation of ammonium salts aerosols (e.g., without SO{sub}2 in the gas), co-injection of ammonia and ozone increased NO conversion to 60 and NO{sub}x removal to 40. However, high NO{sub}x removals were measured in simulated flue gas that contained NH{sub}3, SO{sub}2, and ozone. The total NO{sub}x removal efficiency was 79 when the ammonium salts aerosols were formed in the presence of 2400 ppm SO{sub}2, 312 ppm O{sub}3, and 2900 ppm NH{sub}3. The energy efficiency of collection improved by ～250 for SO{sub}2 removal and more than 4700 for NO{sub}x removal under these conditions. It was determined that the ammonium salts aerosols produced from the reaction of ammonia and sulfur dioxide substantially enhanced total NO{sub}x removal.
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