城市固体废物焚烧飞灰的固化使用活性技术
Chengcheng Fan1, Zhenlin Wu2, Baomin Wang1
1Faculty of Infrastructure Engineering, Dalian University of Technology, Dalian 116024, China.
Journal of environmental management
|November 4, 2023
概括
活性有效地固化城市固体废物焚烧飞灰 (MSWIFA). 添加酸增强了稳定性,显著减少重金属 (Pb, Zn, Cd) 漏,特别是在酸性条件下.
科学领域:
- 环境科学 环境科学
- 材料科学 材料科学 材料科学
- 地质化学 地质化学
背景情况:
- 城市固体废物焚烧飞灰 (MSWIFA) 需要有效的固化/稳定 (S/S) 才能安全处置.
- 性激活是MSWIFA的一个有前途的S/S技术.
- 了解在各种环境条件下从MSWIFA矩阵中出重金属至关重要.
研究的目的:
- 在不同的侵蚀环境下比较研究Pb,Zn和Cd从活性MSWIFA的长期漏行为.
- 评估MSWIFA S/S矩阵中重金属的环境可用性.
- 评估将酸纳入活性化MSWIFA中的稳定作用.
主要方法:
- 用激活的MSWIFA样本的准备和暴露在不同的侵蚀环境中,包括酸雨模拟.
- 长期漏试验以确定重金属 (Pb,Zn,Cd) 的迁移.
- 微观结构和形态分析 (例如,SEM,XRD) 以了解稳定机制.
主要成果:
- 酸性环境严重损坏了MSWIFA S/S矩阵,增加了重金属风险,特别是Cd和Zn.
- 活性MSWIFA/酸表现出增强的结构稳定性和显著降低重金属透性.
- 在MSWIFA/酸样本中,Pb,Zn和Cd的固定效率超过了99.0%.
结论:
- 活性MSWIFA/酸提供了一个稳定的微观结构,具有出色的重金属封装能力.
- 形成弗里德尔盐和C-(A) -S-H凝有助于改善固定.
- 这些发现支持MSWIFA的资源利用和安全填埋.
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