使用氧化和碳酸激活材料稳定和固化,和污染的粘土砂
Alireza Komaei1, Arman Moazami1, Pooria Ghadir2
1Department of Civil and Environmental Engineering, Amirkabir University of Technology, Tehran, Iran.
The Science of the total environment
|May 8, 2025
概括
这项研究使用活性渣和热带石稳定了受重金属污染的土壤,显著增加了强度并减少了污染物出. 这种环保方法为传统稳定技术提供了一个可持续的替代方案.
科学领域:
- 环境工程 环境工程
- 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:
- 工业和采矿活动造成的重金属土壤污染对生态系统和人类健康构成风险.
- 污染的土壤需要有效的稳定和固化,以减轻环境危害.
- 现有的方法可能在性能或环境影响方面存在局限性.
研究的目的:
- 为了研究氧化 (Ca(OH) 2和碳酸 (Na2CO3) 激活的渣和天然焦化在污染的粘土沙中稳定,和的有效性.
- 提高机械强度,降低重金属在受污染的土壤中的透性.
- 评估拟议的稳定方法的环境可持续性.
主要方法:
- 土壤样本被,和污染.
- 通过使用Ca (OH) 2和Na2CO3激活渣和天然热石实现了稳定.
- 进行了不受限制的压力强度 (UCS) 测试以评估机械强度.
- 使用毒性特征漏程序 (TCLP) 来评估金属的漏能力.
- 透性测试测量了液压导电性.
- 通过X射线衍射 (XRD) 和电场发射扫描电子显微镜 (FE-SEM) 分析了微观结构的变化.
- 生命周期评估 (LCA) 将二氧化碳排放与波特兰水泥稳定进行了比较.
主要成果:
- 用20%重量%的Ca ((OH) 2) 和Na2CO3激活渣进行处理,28天后UCS (4449kPa) 增加了75倍,超过了EPA标准.
- 观察到可性显著降低:高达95%,高达92%,高达98%.
- 液压导电率降低了高达97%,表明污染物迁移减少.
- XRD和FE-SEM证实了C(A) SH凝和乙石的形成,有助于增强强度.
- 与波特兰水泥稳定相比,LCA显示二氧化碳排放减少了75%.
结论:
- (OH) 2和Na2CO3激活的渣和焦岩是有效的稳定重金属污染的粘土沙.
- 该方法显著提高了土壤的机械强度,并大大降低了金属的透性.
- 这种方法为传统的土壤稳定技术提供了一个可持续和环保的替代方案,具有较低的二氧化碳排放.
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