Experimental Study And Application Exploration Of Low Temperature SCR Catalyst Reaction In Hazardous Waste Incineration System

At present,the hazardous waste incineration disposal method has become a new hot spot in the process of hazardous waste and harmlessness.The SCR denitration method is the most efficient one among the nitrogen oxide control technologies used in the conventional incineration process,but the common SCR reaction temperature demand is high.If it is applied to the hazardous waste incineration system,under the special environment of high dust,high sulfur,high chlorine or even high fluorine in hazardous waste incineration,it will cause problems such as catalyst blockage and corrosion with the prominent problem of catalyst deactivation,which affects the control effect of long-term emission standards.The purpose of this paper is to screen out the SCR catalyst in the low temperature zone,so that the SCR catalyst can be used in a relatively pure atmosphere after dedusting and deacidification,prolonging the operation cycle and ensuring the denitration effect,which has important practical significance.Based on the previous results,this paper prepared a multi-catalyst Ce/Ti-Al-Si with different Ce loadings by integrated molding method and impregnation method,the denitrification activity test and SO₂/H₂O resistance test were carried out,characterizations such as BET,SEM and XRD were tested.The experimental results show that the low temperature catalysts have denitration activity at 100?,the denitration efficiency reaches 50%when the reaction temperature reaches 140?,and the denitration efficiency reaches 58%at 200?.The high temperature SCR is greatly affected by SO₂ and H₂O.When 5%H₂O+100 ppm SO₂ coexists,the denitration efficiency decreases by nearly 15%,which proves the necessity of deacidification to remove SO₂ and HCl before low temperature SCR catalytic denitration.Based on the experiment of low temperature denitration activity in the low temperature section of the catalyst,this paper takes a hazardous waste incineration disposal project in Zhejiang Province as the exploration object.Through the process design of low temperature catalytic denitration,the parameters of low temperature SCR process are discussed,four schemes such as SGH,DGH,GGH+SGH,GGH+DGH are proposed.Through the industrial analysis and elemental analysis of incineration waste,the system thermal calculation were calculated so as to carry out the feasibility analysis and economic analysis of low temperature catalyst application.The simulation results show that the four schemes can realize the flue gas temperature of the deacidification tower from 60?to 140?,which meets the requirements of the low temperature catalytic temperature reaction range.the economy sexuality of the DGH scheme is not strong,due to the high cost of natural gas;the least annual consumption is the GGH+SGH program,but the smoke resistance is the largest.In this paper,the experimental research on the denitrification performance of low temperature SCR catalysts is carried out to explore the actual flue gas purification scheme for hazardous waste incineration disposal projects.On the basis of meeting the emission standards of flue gas,the equipment loss is reduced,the service life of equipment is prolonged,and the best energy saving and consumption reduction is explored.The application scheme has important reference value for improving the clean emission level of hazardous waste incineration systems.