Insolubilization of lead in MSW fly ash by co-heating with aluminosilicate

抄録

Incineration residues (bottom ash and fly ash) account for about 80% of waste disposed of in landfills. In recent years, the number of landfills which accept fly ash mainly has increased on the back of this situation. Since hazardous heavy metals contained in fly ash are in general easily soluble, leaching suppression treatment is performed in order to dispose it to the controlled-type landfill. The current mainstream is chemical treatment. However, it has been reported that the function of leaching suppression by a chelating agent deteriorates with time, and re-release of heavy metals occurs. The authors confirmed that Cs was specifically trapped in the glassy amorphous phase formed on the surface of alkali feldspar by investigating the incineration process of decontamination waste in previous studies. Thus, in this study, the possibility on whether this trapping mechanism could be applied to insolubilize various heavy metals in fly ash, was set to the target of study. As the results, it was confirmed that aluminosilicates can insolubilize lead in fly ash.