污染土壤的固化/稳定使用活性火山灰
Mohammad Amin Molaei1, Hania Miraki1, Mohsen Morovati1
1School of Civil Engineering, Iran University of Science and Technology, Tehran, Iran.
概括
活性火山灰有效地固定污染的土壤中的,显著增加强度和减少泄漏. 这种环保的替代方案为土壤修复提供了一个有希望的解决方案.
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:
- 土壤中的生物积累对人类健康构成重大风险.
- 使用波特兰水泥进行传统的土壤整治对环境产生不利影响.
- 活性材料 (AAMs) 为土壤稳定和固化 (S/S) 提供了环保的替代方案.
研究的目的:
- 评估AAMs,特别是火山灰 (VA) 在污染土壤的S/S中的有效性.
- 调查VA含量,度,固化温度和土壤修复时间对土壤修复的影响.
- 阐明负责固定的机制.
主要方法:
- 用不同百分比的VA处理了土壤样本.
- 标本经过烤箱固化 (OC) 和环境固化 (AC).
- 评估的属性包括不受限制的压力强度 (UCS),浸出 (TCLP) 和微结构分析 (XRD,FTIR,FESEM/EDS/映射).
主要成果:
- UCS显著增加了15%的VA (OC) 和10%的VA (AC),分别达到600%和458%.
- 在高污染水平下,的出减少了87% (OC) 和91% (AC).
- 通过化学结合,物理封装和不溶性酸盐形成,可以实现有效的固定.
结论:
- 活性火山灰在修复污染的土壤方面表现出色.
- 形成N-A-S-H和酸盐酸盐结构对于S/S机制至关重要.
- 这项研究强调了基于VA的AAM作为传统基于水泥的整治的可持续和有效替代方案.
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