Study On The Denitration Of Flue Gas With Catalytic Oxidation In Ammonia Absorption Process

NOx is one of the main air pollutants for the environmental pollution.It is not only harmful to the human health but also detrimental to the environment and plants.For traditional denitration methods,it is hard to utilize the NOx resources.In addition,the products have more chance to cause secondary pollution to the environment.In this paper,based on the ammonia denitration method,the organic catalysts which are clean,reusable,and stable were selected.The denitration performance and the influencing factors of catalytic oxidation of NOx for these selected catalysts were studied through pilot denitration:1)By detecting the density of the absorbing liquid and the nitrogen concentration in exhaust flue gas,the denitrification performance of the 1#-10#organic catalysts has been compared.The results show that the 4#organic catalyst has better denitrification effect than other organic catalysts.2)Pilot plant of ammonia desulfurization are designed and set up,which is used to continue to demonstrate the denitrification performance within 4#,10#,11#,and 12#organic catalysts.The catalysts are used in the oil refinery.The experimental results demonstrated that the 4#organic catalyst has the best denitrification performance.The recyclability of denitrification and life test of the 4#organic catalyst are discussed.The results show that recyclability of 4#organic catalyst is better than others’.Additionally,its denitration efficiency is maintained unchanged after 48h.3)The influence of the H₂O₂on NO oxidation process were studied.The result indicates that the denitration efficiency reaches 35%when the reaction condition is following:the density of NO is 200ppm,the p H of absorption liquid is 8,the temperature is 50℃,and the introducing rate of H₂O₂is 11ml/L.4)The influence of the O₃on NO oxidation process were studied.The results show that the residence time of ozone has a little influence on the oxidation of NO.When the molar ratio of O₃/NO is 0.7,83.5%NO can be oxidized to NO₂.The oxygen contention within ozone influences the oxidation of NO slightly.When the flue rate is 0.5m³/h,the NO removal efficiency is up to 81%.The optimum p H is 8.The temperature of absorption liquid,range from 20℃to 70℃,has a slight influence on the removal of NO.