Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, 210096, China.
State Key Laboratory of Clean and Efficient Coal-Fired Power Generation and Pollution Control, Nanjing, 210023, China.
Environ Sci Pollut Res Int. 2024 Jul;31(33):45793-45807. doi: 10.1007/s11356-024-33827-4. Epub 2024 Jul 8.
Melting is an efficient method to turn municipal solid waste incineration (MSWI) fly ash (FA) into non-hazardous material. Coal fly ash (CFA) was selected as the silica-alumina source to carry out co-melting research with MSWI FA in this work. The effects of the temperature and the CFA content on mineral transformation and the migration characteristics of heavy metals were analyzed. The results showed that the mixtures of MSWI FA and CFA reacted at high temperatures to mainly generate CaAlSiO, CaSiO, and CaAlSiO primarily and then melted and formed the amorphous-phase vitreous body when the CFA content was more than 40% and the temperature was higher than 1300 °C. During the melting process, Cd and Pb were almost volatilized, while Cr, Mn, and Ni were almost retained. Besides, the volatilization rates of Cu and Zn fluctuated with the temperature and the CFA content. Suitable treatment temperature and CFA content were conducive to the transformation of the heavy metals in the FA into stable forms, and the melting products were no longer hazardous wastes because the vitreous body could effectively encapsulate heavy metals. This study aims to help reuse the FA and CFA collaboratively and be more environmentally friendly.
熔融是将城市固体废物焚烧（MSWI）飞灰（FA）转化为非危险材料的有效方法。本工作选择煤飞灰（CFA）作为硅铝源，与 MSWI FA 进行共熔融研究。分析了温度和 CFA 含量对矿物转化和重金属迁移特性的影响。结果表明，当 CFA 含量大于 40%且温度高于 1300°C 时，MSWI FA 和 CFA 的混合物在高温下反应主要生成 CaAlSiO、CaSiO 和 CaAlSiO，然后熔融并形成无定形玻璃体。在熔融过程中，Cd 和 Pb 几乎挥发，而 Cr、Mn 和 Ni 几乎被保留。此外，Cu 和 Zn 的挥发率随温度和 CFA 含量而波动。合适的处理温度和 CFA 含量有利于 FA 中重金属向稳定形态的转化，熔融产物不再是危险废物，因为玻璃体可以有效地包裹重金属。本研究旨在帮助 FA 和 CFA 协同再利用，实现更环保的目标。
