垃圾焚烧飞灰与玻璃添加剂熔融固化物 相转变研究.

Vitrification of municipal solid waste incineration (MSWI) fly ash is a promising technology to treat hazardous wastes・ The feed-to-glass conversion during the melting solidification process has been of great concern・ Phase transformations of fly ash and the feed (the mixture of fly ash and glass additive) at elevated temperature were analyzed w让h ICP-AES, IC, DSC and XRD・ The results show that the fly ash is mainly composed of Ca, Si, and Cl, and the crystalline phases mainly include hydrous compounds, chlorides, carbonates, and sulfates・ Fly ash occurs dehydration of hydroxides, decomposition o£ carbonates and formation of silicate intermediate phases as the temperatures increased・ After included glass additives (SiO2 and B2O3), the reactions of dehydration and decarbonation could hardly be affected, while the formation of intermediate silicate phases occurs in the lower temperature and the amorphous phase starts to appear in the feed at 850 ・ The feed finally turns to molten glass at 1300 °C ・ Additionally, prolonging the heat-treatment time could promote feed reactions. [ABSTRACT FROM AUTHOR]