Study On The Characteristics Of Simultaneous Desulfurization And Denitrification By Wet Ammonia Process In Packed Towe

Coal as the main energy on industry in our country,accounts for 70%of primary energy sources,the consumption of coal in industry occupies a more larger proportion,Our country’s energy structure determines the style of energy consumption,When the coal is burning,a lot of dust are produced and harmful gas are emited such as SO2 and NOx,when the flue gas and emissions into the air without treatment,it causes a lot of environment problems,such as it become the main factors to form acid rain and photochemical smog.In this article,the absorption solution is ammonia,the absorption equipment is packed tower,Simulation of removal SO2 and NO absorption efficiency into ammonia solution though H2O2 and Fe(II)EDTA were additive into solution were studied.Based on double membrane theory,the model of desulfurization and denitration were derived and validated.Finally,the factors affecting the crystallization of products were studiedThe absorption equipment,packed tower,were designed by us,the absorption solution is ammonia,the absorption solution concentration,initial pH,liquid gas ratio,import concentration of SO2,import concentration of NO,inlet gas velocity,Fe(Ⅱ)EDTA concentration and the H2O2 concentration on desulfurization denitration efficiency were studied in this article,.The results show that increase the absorption liquid concentration,liquid gas ratio the concentration of H2O2 and the concentration of Fe(Ⅱ)EDTA increase the absorption efficiency of removal SO2 and NO,A certain range of concentration of SO2 can promote the absorption of NO.The increasing of the inlet of SO2,the inlet of NO and the inlet of gas velocity all have an negative effect on the removal of SO2 and NO.SO2 removal rate can reach 100%,the NO removal rate can reach 60%on the opportune experimental conditions.The desulphurization and denitration of wet ammonia are analyzed in thermodynamics.Reaction enthalpy was calculated,the calculation results show that desulphurization and denitration of wet ammonia is an exothermic process,increase the temperature has an negative effect on the reaction.Gibbs function of the reaction equation were calculated,the calculation results show that the reactions of wet ammonia desulphurization and denitration can occur spontaneouslyThe mass transfer characteristics of the packed tower were studied,and the equation of gas-liquid mass transfer was used to calculate the material balance.Based on the double-membrane theory,the gas-liquid mass transfer equation of SO2 was derivation,derivation of first-order irreversible denitrification Mathematical Model for Fe(Ⅱ)EDTA complexate absorption NO,The mathematical model refers to the empirical formula of the similarity system in the literature and the specific physical parameters,though the estimation of parameters,to find the solution to the model equation,the trend of the absorption rate with the parameters are obtained,the mathematical model is verified though the model were compared with the experiment results.Although the model has little certain errors,but the errors are within the allowable accuracy of the project.So the mathematical model can provide some theoretical references for the application of wet ammonia desulphurization and denitration in packed tower at the same time.Finally,the crystallization of the product,ammonium sulfate,was studied.The effects of stirring speed,crystallization temperature,pH value and the seed on the crystallization were investigated.At the optimum experimental conditions,the crystallization was carried out at stirring speed of 400 r/min,the temperature of 60℃and the pH of 5.The crystal appearance of ammonium sulfate was observed under electron microscope,and the product was characterized by XRD analy-sis.Through the research of this article,The basic regulas of wet ammonium desulfurization and denitrification at the same time are gained,the reactions’thermodynamic characteristic were analyzed,the model were derivation and solved,the analysis of the factors affecting the crystallization of the product,can provide some theoretical basis for the industrial application.