Positive pulsed corona discharge has been applied for the oxidation of gaseous elemental mercury (Hg0) from a simulated flue gas. The oxidation of Hg0 to HgO and HgCl2 can significantly enhance the mercury removal from flue gas. At a gas condition of O2 (10%), H2O (3%), and N2 (balance), Hg0 oxidation efficiency of 84% was achieved at an input energy density of 45J∕l. The presence of NO, however, hinders Hg0 oxidation due to the preferential reaction of NO with O and O3. On the contrary, SO2 shows little effect on Hg0 oxidation due to its preferential reaction with OH. It has been also observed that the HCl in gas stream can be dissociated to Cl and Cl2 and can induce additional Hg0 oxidation to HgCl2.
This study examines the effect of flue gas components on the oxidation of gaseous elemental mercury (Hg 0 ) to HgO and HgCl 2 via pulsed corona discharge (PCD), where the reaction temperature was set to 908C and the gas stream consisting of 3% H 2 O and 10% O 2 in N 2 was mixed with 45 mg m 73 Hg 0 , 108 ppm NO x , 80 ppm HCl, 200 ppm SO 2 and 470 ppm NH 3 . It has been observed that O 2 and HCl components in the gas stream act as oxidizing precursors through the generation of oxidizing species (O, O 3 , Cl and Cl 2 ) in the PCD process. The presence of NO directly hampers Hg 0 oxidation to HgO due to preferential reaction of NO with O and O 3 . In contrast, the presence of SO 2 indirectly influences the oxidation of Hg 0 to HgCl 2 through the fast reaction of SO 2 with OH radical, resulting in consuming OH radicals which are partially responsible for the formation of chlorine species, i.e. Cl and Cl 2 . It has been also found that NH 3 component significantly hinders the oxidation of Hg 0 to HgCl 2 through the fast acidbase reaction with HCl.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.