Study On Low Temperature Selective Catalytic Reduction Denitration Catalyst For Flue Gas

With the development of industrialization,the air quality is getting worse.Especially in recent years,environmental problems has attracting more and more people's attention,and the controlling to environmental pollution among every country has becoming serious.Nitrogen oxides,the main source of air pollution,has caused serious threat to the human survival,which urgently needs to be controlled.Currently,the general measures to control nitrogen oxides is the low-NOx burning and De-NOx after fuel combustion.The Selective Catalytic Reduction,among these De-NOx technologies,is the most widely applied and the most worldly recognized.Currently theactivation temperature of the commercial vanadium and titanium based catalyst is generally 300?420?,and there is no catalytic activity when the temperature is below 300?.Therefore,it generally requires the catalyst disposed between the economizer and preheater.However,between the economizer and preheater,there contains a lot of dust,in which a large amount of substance,such as alkali metals,arsenic and mercury,etc,can poison the catalyst and serious affect the life of catalyst.Therefore,the development of catalyst,which could be placed after the dust collector and could be provided with a low-temperature activity,is becoming of great significance.In this case,the article systematically studies the low-temperature SCR flue gas De-NOx technology.Specific work and experimental results describe as below.First of all,our research group designs and sets up a simulation apparatus of flue gas producing andexperimental apparatus of flue gas De-NOx.The simulation apparatus takes a variety of gas cylinder as the gas source and proportionally mixes various gases to simulate flue gas of actual fuel combustion.And the latterapparatus is set up to detect the performance of self-designed catalyst of low-temperature SCR flue gas De-NOx in every indicator.Secondly,we detect the capability of self-designed catalyst of low-temperature SCR flue gas De-NOx according to the designated experimental conditions.Besides,through the analysis of factors of catalyst component,experiment indicator,De-NOx performance and so on.We conclude the lever of various influencing factors to the De-NOx performance,so as to guide the adjustment of the added amount of catalyst components.Finally we get the self-designed catalyst of the best performance of De-NOx through continuous experimentation.Data are as follows:w(MnC2O4·2H2o)=1 8%,w(Ni(No3)2·6H2o)=5%,w(Cro3)=9%,w(NH4Vo3)=10%,w(Fe(No3)3·9H2o)=15%,w(Ceo2)=3%,w(Wo3)=2%,w(?-Al2O3)=38%,the temperature of the De-NOx reaction is:170?-250?.When testing the performance of sulfur resistance to the self-designed catalyst,it could maintain a good De-NOx function while the concentration of SO2 is under 150mg/Nm3.When the catalyst is put into operation,the most economical ratio of ammonia nitrogen is 0.95,the suitable range for airspeed selection is 3000-5600h-1,the appropriate conditions for the oxygen content is 3.0%-4.5%,and the initial concentration of NOx need to be controlled under 1000mg/Nm3.