Le Forestier Lydie, Libourel Guy
ISTO, UMR 6113 CNRS-Université d'Orléans, Polytech'Orléans, 8 rue Léonard de Vinci, 45072 Orléans cedex 2, France.
J Hazard Mater. 2008 Jun 15;154(1-3):373-80. doi: 10.1016/j.jhazmat.2007.10.034. Epub 2007 Oct 18.
Municipal solid waste (MSW) flue gas residues require further treatment prior to disposal or reuse, and vitrification is one of the main solidification-stabilization processes. This paper investigates the high temperature behavior of MSW flue gas residues, performed in laboratory experiments up to 1400 degrees C, and coupled with thermogravimetric analyses, X-ray diffraction, chemical and electron microprobe analyses. Melting temperatures of electrostatic precipitator (ESP) ash are in the range of 1202-1272 degrees C, whereas semi-dry scrubber residues melt between 1900 and 2300 degrees C. We show that the mean liquidus temperature of flue gas residues can be simply evaluated from their CaO content, by using the CaOSiO2Al2O3 ternary diagram. For ESP ash, the liquidus phase is a Zn-rich aluminous spinel, followed by anorthite at 1225 degrees C, and melilite at 1190 degrees C. The total mass loss reaches 18 wt.% at 1300 degrees C. Moreover, 90% of evaporation takes place below 1000 degrees C, linked to evaporation of C, Cl, S, Na, K, and of the toxic metals Hg, Cd, Pb, Cu. Due to the high partial pressure of chlorine during heating, chloride is the most probable form of evaporation for Cd, Pb, and Cu. However, most of Zn, Cr, Ni, Sb and Sn remain in the vitrified product.
城市固体废弃物（MSW）烟道气残渣在处置或再利用之前需要进一步处理，而玻璃化是主要的固化稳定化工艺之一。本文研究了MSW烟道气残渣在高达1400℃的实验室实验中的高温行为，并结合热重分析、X射线衍射、化学分析和电子微探针分析。静电除尘器（ESP）灰的熔化温度在1202 - 1272℃范围内，而半干式洗涤器残渣在1900至2300℃之间熔化。我们表明，通过使用CaO-SiO₂-Al₂O₃三元相图，可以根据烟道气残渣的CaO含量简单评估其平均液相线温度。对于ESP灰，液相线相是富含锌的铝尖晶石，在1225℃时为钙长石，在1190℃时为黄长石。在1300℃时总质量损失达到18 wt.%。此外，90%的蒸发发生在1000℃以下，这与C、Cl、S、Na、K以及有毒金属Hg、Cd、Pb、Cu的蒸发有关。由于加热过程中氯的分压较高，氯化物是Cd、Pb和Cu最可能的蒸发形式。然而，大部分Zn、Cr、Ni、Sb和Sn保留在玻璃化产物中。
