Study On The Migration And Distribution Of Pb And Cu During The Process Of Municipal Solid Waste Incineration

With the development of Chinese economy and the accelerated process of urbanization,the output of municipal solid waste is increasing year by year.Heavy metals produced in the process of waste incineration have caused great harm to the ecological environment and human health.Therefore,it is of great practical significance to study the migration and distribution of heavy metals in the process of waste incineration and the rational selection of additives in order to reduce the emission of heavy metals.This thesis takes municipal solid waste in Shanghai as the research object and a tube of SK2-4-12 type is adopted to simulate waste incineration process.Studying the influence of chloride,sulfide and oxide on the migration and distribution of heavy metal Pb and Cu in municipal solid waste during four incineration temperatures by experimental method.Inductively coupled plasma atomic emission spectrometry(ICP-AES)was used to measure the content of heavy metal after collection and digestion of incineration products.Then the distribution characteristics of Pb and Cu was obtained with different temperature conditions and additives.The experimental results showed that adding chloride could promote the volatilization of Pb.The three kinds of chlorides promoted the ability of volatilization of Pb under the same temperature,the capacities vary as PVC>NaCl>KCl.The effects of sulfide on the volatilization performance of Pb was that when the temperature is 600 ℃,S,Na2S and Na2SO4 can reduce the volatilization of Pb,and the ability varied as S>Na2S>Na2SO4.When the temperature is 700 ℃,S can reduce the volatilization of Pb while Na2S and Na2SO4 promote it,the ability was Na2SO4>Na2S.When the temperature is 800 ℃,900℃,S,Na2S and Na2SO4 could promote the volatilization of Pb,the ability was Na2S04>Na2S>S.For all the three kinds of oxides,the volatilization of Pb is weakened with the increase in added quantities and at the same temperature the capture varns as SiO2>CaO>Al2O3.The addition of chloride could also promote the volatilization of Cu.When the temperature is 600℃,700℃ and 800℃,the evaporation capacities of the three kinds of chlorides vary as PVC>NaCl>KCl.However,when the temperature is 900 ℃,it changed as NaCl>PVC>KC1.The effects of three kinds of sulfide on the volatilization of Cu as follows,when the burning temperature is 600 ℃,700 ℃,S and Na2S can reduce the volatilization of Cu,the ability was S>Na2S,but Na2SO4 would promote the volatilization of Cu.When the incineration temperature is 800℃,900℃,S could reduce the volatilization of Cu,while Na2S and Na2SO4 promoted the volatilization of Cu,the ability was Na2SO4>Na2S.At the same temperature,for the three kinds of oxides,the volatilization of Cu is weakened with the increase in added quantities and the capture varies as SiO2>CaO>Al2O3.In addition,the Equilibrium Composition module in HSC Chemistry software is used to simulate and calculate the morphology and distribution of heavy metals in the process of combustion.The conversion mechanism of using simulation results of heavy metals in the incineration process were further elaborated,forther verification and analysis of the distribution characteristics of the incineration process Pb,Cu and the effects of various additives,for the reasonable selection of additives to reduce the heavy metal pollution provides a theoretical basis for the.