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Due to expected more stringent emission standards there is a lot of scientific development focused on the development of the mercury removal technologies,mainly directed in two alternatives; the enhancement of homogenous oxidation of Hg0 to soluble Hg2+ in flue gases by the addition of chlorides or bromides into the boiler or the adsorption of Hg2+ and Hg0 on the impregnated activated carbon(AC).Third option gaining more attention lately is the possibility to modify the wet FGD to oxidize dissolved Hg0 and retain it in the wet FGD.The chemistry of wet FGD is very complex one including equilibriums in gas/aqueous and in aqueous/solid interfaces and equilibriums and kinetics in the aqueous solution.The parametric study was performed to quantify the influence of different parameters on the removal efficiency of Hg0 from the gaseous phase.For wet FGD(WFGD)it was widely accepted that oxidized Hg is retained in FGD solution by dissolution,while elemental Hg usually passes the WFGD to the atmosphere.In our extensive research it was found that WFGD chemistry can be modified so that elemental Hg can be oxidized by air introduced for oxidation of sulphur dioxide to gypsum.The fate of Hg bound to solid phase has also been investigated.Elemental Hg removal efficiency from flue gas from 60 to over 90%has been achieved.Up to 90%of total Hg in solid phase has been removed by small stream of solid phase,which represents about 10%of total solid phase.Preliminary comparative cost estimates have been prepared for two of commercial processes and the one in development showing that there is a great saving potential for the alternative process.