Mercury removal from simulated coal-fired power plant flue gas using UV irradiation and silica-titania composites.

摘要

Mercury is listed as a hazardous air pollutant (HAP) because of its adverse health effects on humans. Without technologies that effectively remove mercury that is contained in the flue gas of coal combustion power plants, the long-term effects on the nation's health could be catastrophic.;This research builds on previous work to examine mercury removal at typical flue gas temperatures (up to 375°F), multiple flue gas components (SO 2, NO2, HCl), and short contact times (0.3--2 s) by studying photocatalytic oxidation and capture of mercury by a silica-titania composite technology coated onto ceramic packing material. Experiments conducted under flue gas conditions showed little change in Hg removal performance when the temperature was increased from 275°F to 375°F. Both oxidation and adsorption seemed to be inhibited by moisture at 375°F, except when chlorine was present. Moisture had a significant detrimental effect on oxidation levels of mercury by UV alone, particularly at a wavelength of 254 nm.