A Study On Environmental Risk Control Of Domestic Waste Incineration And Disposal

Nowadays incineration is a commonly used method for the disposal of domestic waste.Incineration has become one of the widely used methods at home and abroad for its advantages of harmlessness,capacity reduction and resource utilization.However,how to eliminate the harmful effects of dioxin and other pollutants on the environment has become a hot issue in environmental engineering and environmental science research.In this paper,Suihua Municipal Domestic Waste Incineration Plant was selected as the research object.Through the identification of environmental pollution factors,especially environmental risk factors,appropriate mathematical models were used to study the adverse effects of harmful pollutants in domestic waste incineration flue gas on the environment,and then effective measures to mitigate the impact of atmospheric environment were put forward.It provides scientific guidance for avoiding environmental problems during the operation of the incineration plant.Firstly,on the basis of investigating the production process of the domestic waste incineration plant,the environmental impact factors were identified by using the verification table method,indicating that besides SO₂,NO₂ and particulate pollutants,HCl and even dioxin pollutants may be produced in the flue gas.Because dioxins have potential toxicity characteristics,this paper focuses on screening them as characteristic pollutants.Secondly,the AERMOD prediction model is used to predict the environmental impact range and impact degree under normal and abnormal operating conditions of domestic waste incineration project.The results show that the maximum ground concentration of dioxin pollutants in the environment can meet the requirements of environmental quality standard limits after the furnace"3T"control technology is adopted.However,the environmental impact under abnormal operating conditions is significantly increased compared with that under normal conditions.The results of the"four-step"health risk assessment showed that the exposure concentration of dioxin to the protection target area reached 0.288 pg TEQ/m³ while the value of dioxin inhaled to the human body was 6.912×10^-3pgTEQ/kg,accounting for 1.73%of the standard limit of human health risk.Finally,on the basis of"3T"dioxin control technology in the furnace in the garbage incineration process,the control measures for flue gas outside the furnace are further proposed,namely"SNCR+semi-dry method+activated carbon adsorption+bag filter"purification technology for flue gas control.Therefore,on the premise that the flue gas temperature in the furnace is more than 850℃,the residence time in the high temperature zone in the flue gas furnace is more than or equal to 2s,and dioxin is fully decomposed by turbulent flow,other harmful pollutants in the flue gas can be effectively removed.Engineering practice shows that the concentration of dioxin and other pollutants in flue gas can meet the requirements of"Pollution Control Standard for Domestic Waste Incineration"（GB18485-2014）after adopting the above control measures.