固化/稳定和优化城市固体废物焚烧的飞灰与酸固体废物
Chengcheng Fan1, Weigao Ding1, Baomin Wang1
1School of Infrastructure Engineering, Dalian University of Technology, Dalian, 116024, China.
Journal of environmental management
|April 5, 2024
概括
将酸固体废物添加到活性化城市固体废物焚烧飞灰 (MSWIFA) 中,可以提高结构稳定性并减少重金属的毒性. 这种优化增强了MSWIFA的固化/稳定性,使其成为更安全的材料.
科学领域:
- 材料科学 材料科学 材料科学
- 环境工程 环境工程
- 地质化学 地质化学
背景情况:
- 活性化是固化和稳定城市固体废物焚烧飞灰 (MSWIFA) 的关键技术.
- 富含,缺乏的MSWIFA相导致活性体的结构不稳定性和污染问题.
- 优化MSWIFA固化需要解决其固有的材料特性.
研究的目的:
- 为了增强活性化MSWIFA的结构性质和重金属固定性.
- 研究将酸固体废物纳入MSWIFA固化/稳定 (S/S) 性能的影响.
- 为MSWIFA S/S矩阵的资源利用提供理论基础.
主要方法:
- 将酸固体废物 (煤炭飞灰,烟,颗粒高炉渣) 纳入MSWIFA.
- 活性化工艺用于MSWIFA和固体废物的混合物.
- 压力强度和重金属可性 (Pb, Zn, Cd) 的评估.
- 使用XRD和SEM (隐含) 等技术分析相位组成和微观结构.
主要成果:
- 添加酸固体废弃物显著改善了压力强度 (28天后增加31.0-50.8%).
- 重金属 (Pb,Zn,Cd) 的性降低,低于标准值 (GB16889).
- 检测到新的阶段 (乙三,硫氨酸酸盐,弗里德尔盐) 和增加的无形阶段,增强结构完整性.
结论:
- 酸固体废物有效地优化了活性化MSWIFA的结构性质和重金属固定.
- 加入Si/Al结构单元有助于形成稳定的网络结构和凝.
- 本研究提供了一个可行的策略,通过增强的S/S技术来利用MSWIFA的资源.
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