Enhanced Mercury Oxidation

摘要

In March 2005, the US Environmental Protection Agency announced two rules for air pollution that apply to coal-fired power plants: the Clean Air Interstate Rule and the Clean Air Mercury Rule. Although a number of technologies have been demonstrated to reduce mercury emissions such as activated carbon injection, it has been determined that significant reduction of mercury removal can be achieved in flue gas desulfurization FGD systems. Increased mercury oxidation upstream of the FGD system will facilitate higher overall mercury removal for the plant. Selective catalytic reduction (SCR) catalyst has been shown to significantly increase mercury oxidation by converting elemental mercury to (Hg0) to Hg2+ in coal combustion flue gases. New SCR catalyst has also been developed for bituminous fuel applications, resulting in improved mercury (Hg0) oxidation activity while maintaining low SO2 to SO3 conversion. The performance of this new catalyst has been confirmed using laboratory-scale test apparatus and a 1 MW thermal pilot plant.