酸性侵蚀对固化污水污泥特性的影响
Xihui Fan1,2, Haoqing Xu3,4, Yiyan Lv5
1School of Architecture and Civil Engineering, Jiangsu University of Science and Technology, Zhenjiang, 212100, China.
Environmental science and pollution research international
|August 10, 2023
概括
固化污泥显示出作为填埋场覆盖面的潜力. 然而,酸性条件增加了的出水,而的出水保持稳定,这表明这两种金属的迁移风险很低.
科学领域:
- 环境科学 环境科学
- 地质技术工程 地质技术工程
- 材料科学 材料科学 材料科学
背景情况:
- 固化污泥是家庭垃圾填埋场潜在的土壤覆盖材料.
- 垃圾填埋场的酸性液对垃圾填埋场施工中使用的水泥基材料构成威胁.
- 了解固化污泥在酸性环境中的浸出行为对于评估其长期稳定性至关重要.
研究的目的:
- 在不同的pH条件下研究凝固的污泥成分的浸出过程.
- 评估固化污泥在酸性环境中的恶化风险.
- 测定pH值对 (Ni) 和 (Cr) 浸出和扩散的影响.
主要方法:
- 使用半动态漏试验来模拟填埋场条件.
- 固化污泥样本暴露于不同的pH值 (强酸性,弱酸性和几乎中性).
- 在液中测量了 (Ni) 和 (Cr) 度,以评估漏率和扩散系数.
主要成果:
- 在强烈酸性环境 (pH = 2) 中, (Cr) 泄漏率显著增加,扩散系数上升了一个数量级.
- (Ni) 浸出和扩散系数对水泥含量和pH值变化表现出最小的敏感性.
- 和Cr都表现出相对较低的整体迁移比率从固化污泥.
结论:
- 固化污泥的稳定性取决于pH值,特别是在浸方面.
- 在固化污泥中的行为不受酸性条件和水泥含量的影响.
- 和Cr的低迁移比率表明,使用固化污泥作为填埋场覆盖材料的风险是可以管理的,前提是考虑pH的影响.
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