title: Mechanochemically induced synthesis of anorthite in MSWI fly ash with kaolin.
abstract: The process of mechanical milling has been found to effectively stabilize heavy metals in municipal solid waste incinerator (MSWI) fly ash, as well as to restrain the evaporation of heavy metals during thermo-treatment. This method is adopted in this study and the composition and degree of amorphization adjusted to improve the efficiency of crystalline anorthite synthesis. Different milling times (1, 5, 10 and 20 h) and different sintering temperatures (900, 950, 1000, 1100, 1200 and 1300 °C) are utilized. The extracted fly ash and kaolin (KEFA) were mixed to simulate an anorthite composite. The experimental results indicate that the degree of amorphization of the KEFA increased as the milling time increased. Furthermore, the synthesis of crystalline anorthite increased as the degree of amorphization increased. The milling process allowed a reduction in the synthesization temperature from 1300 °C to 950 °C. The heavy metals are sealed in during the liquid sintering phase, which reduces the amount of heavy metals released from the sintered specimens.
authors.affiliation: Department of Water Resources and Environmental Engineering, Tamkang University, No. 151, Yingzhuan Rd., Tamsui Dist., New Taipei City 251, Taiwan, ROC.
authors.forename: Ching-Wei
authors.initials: CW
authors.lastname: Wu
authors.forename: Chang-Jung
authors.initials: CJ
authors.lastname: Sun
authors.forename: Sue-Huai
authors.initials: SH
authors.lastname: Gau
authors.forename: Cheng-Lin
authors.initials: CL
authors.lastname: Hong
authors.forename: Cheng-Gang
authors.initials: CG
authors.lastname: Chen
mesh_terms: D000538:Aluminum Silicates / Q000032:analysis / Q000737:chemistry*; D060729:Coal Ash / Q000032:analysis / Q000737:chemistry*; D004785:Environmental Pollutants / Q000032:analysis / Q000737:chemistry*; D017745:Incineration; D007616:Kaolin / Q000737:chemistry*; D019216:Metals, Heavy / Q000032:analysis; D008855:Microscopy, Electron, Scanning; D010316:Particle Size; D013696:Temperature; D014961:X-Ray Diffraction
chemical_list: D000538:Aluminum Silicates; D060729:Coal Ash; D004785:Environmental Pollutants; D019216:Metals, Heavy; C074225:anorthite; D007616:Kaolin