Simulation of the Radiation-Chemical Conversion of Mercury Vapor in Power-Plant Flue Gases in the Presence of Hydrogen Chloride

The effect of HCl on the conversion of mercury vapor in the electron-beam treatment of power-plant flue gases for removing nitrogen and sulfur oxides was investigated. A kinetic scheme for the process consists of the liquid-phase oxidation of Hg by O₃molecules and OH radicals followed by the adsorption of liquid-phase oxidation products on soot particles, which are removed from the gas flow using filters. It was found that almost complete removal of mercury vapor is attained at typical radiation doses and process temperatures at soot concentrations higher than 100 g/m³(STP). At a soot concentration lower than 100 g/m³(STP) and an HCl concentration higher than 50 mg/m³(STP) in the gas phase, biologically active HgCl₂is formed in considerable amounts.