| Sulfur dioxide removal from flue gas by catalytic oxidation containing transitional metal ions in aqueous solution has become an important research aspect in the sort of reclaimable desulfurization techniques, usually in which main byproduct H2SO4 is produced. Techniques of dilute H2SO4 and ammonia neutralization are classified by means of the way of dealing with tSCU. Among those techniques, H2SO4 is utilized after emission at certain concentration in the technique of dilute H2SO4 the process of desulfurization is carried through in high acidic condition, in order to acquire high SO2 removal efficiency operating and running cost is increased. Although the process of desulfurization can be controlled at high pH to run by adding ammonia to neutralize H2S04 and high additional valuable byproduct can be produced in the technique of ammonia neutralization. It is only applicable to the regions where ammonia is abundant and the demand of compound fertilizer is large and has the disadvantage of ammonia loss through volatilization. When scrap iron is deposited in absorbent tank, H2SO4 is neutralized and FeSO>4 is yielded as water treatment agent. The technology can achieve the multipurpose to deal with scrap iron, sulfur dioxide in fuel gas and wastewater, which has wider exploitation and application future. So far, the technology is only mentioned in one literature. On the basis of analyzing synthetically the above techniques, a superior technology of flue gas desulfurization by scrap iron is presented. The main contents of this paper are as follows:1. It is necessary for absorbent whose iron ion concentration is close to saturation to discharge from desulfurization absorbent cycle to evaporation crystallization system in view of economic, because FeSO4 is the expected byproduct in the technology of flue gas desulfurization by scrap iron. The open report of the SC2 removal efficiency in so high iron ion concentration absorbent without other catalysis is not found hitherto. So the SO2 removal efficiency is discussed in high concentration FeS04 solution while scrap iron and other catalyst is inexistent. The influence magnitude of each factor on SOi removal efficiency is ascertained through orthogonal experiment. After that the effect of the superficial gas flow rate, absorption temperature and SO2 inlet mass concentration on SO2 removal efficiency is further studied. Finally, the continuous experiment is conducted in the elected conditions toinvestigate the variational rules of SO2 removal efficiency and absorbent pH with reaction time.2. After the feasibility of desulfurization in high concentration FeSO4 solution is validated, it is inevitable to further investigate the actual operating characteristic of flue gas desulfurization by scrap iron. So FeS04 solution and tap water individually are used to remove sulfur dioxide from flue gas without other catalysis. Scrap iron is deposited in absorbent tank. The continuous experiment is conducted to find the change of SO2 removal efficiency and absorbent pH with reaction time and the process of mass transfer-reaction is analyzed. Furthermore, the change of total iron molar concentration in absorbent with time and the effect of initial FeSO4 molar concentration on SO2 removal efficiency and absorbent pH are investigated to analyze the feasibility of the technology. Meanwhile, The influence magnitude of each factor on SO2 removal efficiency and absorbent pH is investigated. Finally, SO2 removal efficiency empirical equation in the scope of experimental condition is gained from the result of uniform experiments by means of stepwise regression analysis.3. Under the basis of the experimental results in lab, crossflow packed-bed absorber for additional experiment is designed according to experience. The dimension of packed-bed absorber is fixed and flooding gas speed of absorber is checkouted. At the same time, calandria liquid distributor is designed. The efficiency of flue gas desulfurization by scrap iron is investigated in the additional equipment. Under th...
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