混合均性对基于水泥的固化污染粘土的浸出行为产生影响
Tingting Deng1, Marsheal Fisonga1, Han Ke2
1Institute of Geotechnical Engineering, School of Transportation, Southeast University, Nanjing 211189, China.
The Science of the total environment
|October 22, 2023
概括
在水泥固化污染的粘土中改善的混合均性减少了 (Pb2+) 浸出. 更好的统一性限制了污染物迁移,提高了固化废物的安全性. 这项研究量化了统一性.
科学领域:
- 地质技术工程 地质技术工程
- 环境科学 环境科学
- 材料科学 材料科学 材料科学
背景情况:
- 混合均性对于水泥固化污染的粘土的质量控制至关重要.
- 了解混合均性对污染物漏的影响对于安全的废物处理至关重要.
- (Pb2+) 是污染场所常见的污染物,需要对其固化行为进行研究.
研究的目的:
- 提出一种定量方法来描述固化受污染的粘土中的混合均性.
- 为了研究混合均性对Pb2+从水泥固化粘土中的浸出行为的影响.
- 使用X射线计算机断层扫描 (X-CT) 分析固化矩阵的内部结构.
主要方法:
- 开发了一种定量方法来描述混合均性.
- 进行了漏毒性测试和半动态漏测试,以评估Pb2+漏.
- 利用X射线计算机断层扫描 (X-CT) 可视化固化样本的内部介质镜结构.
主要成果:
- 漂水毒性测试显示了与混合均性无关的显著Pb2+度偏差.
- 半动态漏试验显示,Pb2+的累积漏质量和扩散系数随着混合均性的增加而下降.
- X-CT分析表明异质结构具有高水泥区封装低水泥区高水泥区.
结论:
- 混合均性显著影响Pb2+迁移在水泥固化污染的粘土中,特别是在半动态漏中.
- 由于样本破坏和代表性问题,现有的漏毒性测试预处理方法可能不足.
- 增强的混合均性通过创建更连续的固化矩阵来改善Pb2+的制.
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