| Sintering process is an important part of steel production, which produces flue gascontaining large amount of pollutants. Among these pollutants, SO2and NOXaccount forlarge proportions of more than70%and45%of the total emission in the steel industry,which are still increasing every year, having caused serious environmental problems. Inthis paper, based on the ammonia desulfurization process, a new synchronizeddesulfurization and denitrification technique using ammonia-complexing agent methodwas proposed, and a pilot system with a flue gas treatment capacity of120Nm3/h wasdesigned and manufactured.The results indicated that by increasing the Fe(II)EDTA concentration, reducing thereaction temperature and the intake air flow, the desulfurization and denitrificationefficiency could be improved. The desulfurization and denitrification effect underalkaline condition was most stable and durable. When the Fe(II)EDTA concentration was0.075mol/L, the desulfurization and denitrification rates were90％and56％. With theFe(II)EDTA concentration increased to0.100mol/L, the desulfurization anddenitrification rates would increase, but only slightly. When the temperature was set at40℃, the desulfurizationand denitrification rates were86％and56％; When the initialpH was8, the desulfurization rate was99％, the denitrification rate was50％; When theintake air flow was50L/h, the desulfurization rate was94％, and the denitrification ratewas71％. The optimum operation parameters were50℃, pH=8,50L/hof intake air flow,and0.075mol/L of Fe(II)EDTA. Under this condition, the desulfurization rate wouldapproximately reach100%, and denitrification rate was above60%within7hours. Inaddition, the forced oxidation of (NH4)2SO3was also studied in this paper. The resultsshowed that the subacidity condition was conducive to the forced oxidation; the elevationof concentrations of SO2-2-3and SO4was not conducive to the oxidation, and the increaseof intake air flow and temperature was conducive to the forced oxidation. |
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