| Nowadays,the pollution of sulfur dioxide which produced by coal-fired power plant has been concerned seriously.The flue gas desulfurization（FGD） is an effective way to control the emitted sulfur dioxide,and the ammonia FGD is one of the most extensively used technology for desulfurization,and its dominating by-product is ammonium sulfite（（NH4）2SO3） which is instable.If（NH4）2SO3 is regarded as chemical fertilizer or industrial raw material,it will decompose to sulfur dioxide,which will bring secondary pollution;if （NH4）2SO3 is oxidized to（NH4）2SO4,it can solve the problem of secondary pollution,and（NH4）25O4 has good economic benefits.At present,the common method of oxidizing（NH4）2SO3 is oxygen oxidation method,this method has a long oxidation period,only can oxidize low concentration.In this paper（NH4）2SO3 is oxidized by ozone process,which is a better solution to this problem.The effect of oxidation between ozone and oxygen were compared. The factors of ozone oxidizing（NH4）2SO3 effects are investigated,such as the ozone flow（0.0045～0.0118 mol/min）,the initial concentration of （NH4）2SO3（1.0～2.5 mol/L）,the initial pH value（4～10）,the reaction temperature（293.15～323.15 K）,circular flux of solution（4～7 L/min）. Through orthogonal experiment,the best reaction condition in the scope of the experiment was found out.They were studied that the energy and kinetics in reaction process.Study showed that:ozone oxidation process was much better than oxygen oxidation process.With the increase of the ozone flow,the oxidation rates of（NH4）2SO3 increased greatly;with the increase of the initial concentration,oxidation rates decreased;with the increase of the temperature,oxidation rates increased,but the growth rate reduced;with the increase of the initial pH value,oxidation rates increased,with the increase of the circular flux of solution,oxidation rates increased little. With the increase of injection power,the conversion rate of（NH4）2SO3 gradually increased.Through orthogonal experiment,the order of factors was:ozone flow＞（NH4）2SO3 concentration＞temperature＞pH value＞circle flux.The Optimal factor was that ozone concentration was 0.0118mol/min, （NH4）2SO3 concentration was 1.0 mol/L,the temperature was 323.15K, the circle flux was 5.5 L/min,and the initial pH value was 6. On the base of Arrhenius equation,the kinetic model was established. Graph was made with experimental data,and it showed that the process of ozone oxidizing（NH4）2SO3 fit first-order kinetics,the linear coefficient was above 0.98.Ozone technology can oxidize concentrated（NH4）2SO3 efficiently and economically,which provides a technology infrastructure for ammonia FGD. |
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