The migration and transformation characteristics of Pb and Cd in domestic solid waste incineration system
In order to clarify the migration and transformation characteristics of Pb and Cd in the solid waste incineration system,a municipal solid waste incineration system with a treatment scale of 500 t/d was used as the research object,and in-depth analysis of the enrichment characteristics,leaching toxicity and occurrence forms of Pb and Cd in the ash generated at different locations in the solid waste incineration system were carried out.The results showed that the main crystalline phase minerals in the bottom ash and the second and third flue ash were SiO2 and CaCO3,and the main crystalline phase minerals in the horizontal flue ash and the tail flue ash were SiO2,KCl,NaCl,CaCO3,and CaSO4,and CaOHCl in the bag filter ash was the product formed during the absorption of HCl by Ca(OH)2;Cd and Pb were enriched to the highest degree in the tail flue ash and bag filter ash respectively,and the leaching concentrations of Cd in the horizontal flue ash,Pb and Cd in the tail flue ash and bag filter ash were higher than the limiting standards of"Identification standards for hazardous wastes-identification for extraction toxicity"(GB 5085.3-2007);Pb existed in various forms in the bottom ash and second and third flue ash,while Pb in the horizontal flue ash and tail flue ash mainly existed in the form of residue.As the flue gas temperature decreased,the acid soluble Pb content in the tail flue ash and bag filter ash increased.Cd in bottom ash and second and third flue ash mainly existed in reducible and residual forms,while Cd in horizontal flue ash and tail flue ash mainly existed in acid soluble form.The acid soluble Cd in bag filter ash was significantly reduced and mainly existed in reducible form.
solid waste incinerationPbCdenrichment characteristicsleaching toxicityexistence form
NETL
NSTL
万方数据
