Study On The Effects Of Adsorbents And Catalysts On Flue Gas Denitration In Dielectric Barrier Discharge

Nitrogen oxide removing process in flue gases is one of important problems for environmental protection.Dielectric barrier discharge technology has been used to study the NO removal efficiency in simulated industrial flue gas in the paper.The following denitration methods have been studied by using biomass（industrial sawdust and crop straws）and its modification,mineral adsorbents（diatomite,bentonite,kaolin and zeolite）and catalysts（manganese dioxide and molecular sieves）.The utilization of biomass modification can realize the recycling of resources.The main conclusions of this experiment are as follows:1.Firstly,the power parameters of the reactor are studied based on characteristics of industrial flue gas.Research results show that when the optimal power frequency of the experimental system is 9.1 k Hz,the minimum voltage at which the power reactor discharge reaches to the breakdown point of 20 V.Secondly,influences of parameters of the flue gas on NO removal efficiency and NO₂generating efficiency are studied.The results show that in the N₂ and NO atmosphere conditions,different volume fractions of oxygen are introduced,and the NO removal efficiency is the best when the volume fraction of oxygen is 7%.When C₂H₄is passed into flue gas component,the NO removal efficiency and the NO₂generating efficiency can be improved obviously by increasing appropriate C₂H₄ concentration.2.Industrial sawdust and crop straws are added to the reactor.The order of NO removal efficiency under different added materials is as following sequences:industrial sawdust>corn straw>rice straw>wheat straw>no fillings,respectively.Next,industrial sawdust and three kinds of straws are modified by alkali,acid and hydrothermal.And the effect of modified biomass added to DBD reactor on NO removal efficiency is studied.The experimental results show that with the conditions of industrial sawdust treated with 1%HCl solution,corn straw treated with hydrothermal treatment for 4h,rice straw treated with 3% HCl solution,and wheat straw treated with 4%HCl solution,the NO removal efficiency can reach to the best level.It also can obviously promote the NO₂ generating efficiency at the same time.3.Adding mineral adsorbents and catalysts to the reactor for removing NO,it is found that NO removal efficiency is significantly promoted when diatomite and manganese dioxide are filled in the discharging section.4.We combine the catalyst with the adsorbent material in the experiment by combining MnO₂with diatomite,combining MnO₂ with industrial sawdust treated with 1%HCl solution,combining MnO₂ with corn straw with hydrothermal treatment for 4 hours,combining MnO₂with rice straw treated with 3%HCl solution and combining MnO₂with wheat straw treated with 4%HCl solution,respectively.After combining the catalyst with the adsorbent,NO removal efficiency and NO₂generating efficiency are both more significantly increased compared with the original efficiency.The highest NO removal efficiency can reach to 87%.