通过生物炭水泥固化提高污染土壤的道路性能:一项实验性研究
Zhenjie Zou1, Yinghong Qin1, Tongsheng Zhang2
1College of Civil Engineering and Architecture, Guangxi University, 100 University Road, Nanning, Guangxi, 530004, China.
Journal of environmental management
|October 16, 2023
概括
这项研究表明,生物炭-水泥复合材料有效地处理受污染的土壤. 添加1-5%的生物炭可以提高土壤的强度,减少重金属的漏,提供了一个有前途的修复技术.
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:
- 基于水泥的固化对于重金属的修复是有效的,但与高污染水平作斗争.
- (Pb2+) 污染对环境和健康构成重大风险.
- 开发增强型固化剂对于有效的土壤整治至关重要.
研究的目的:
- 为了研究生物炭水泥复合物的有效性,作为Pb2+污染土壤的固化剂.
- 评估不同生物炭含量对固化土壤物理和化学性质的影响.
- 评估这种复合材料作为次级填充材料的潜力.
主要方法:
- 准备的生物炭-水泥复合样本具有不同的生物炭百分比 (1-5 wt%).
- 评估材料性能,包括透性,不受限制的压力强度 (UCS) 和漏特性.
- 分析了与中国危险废物标准相比,Pb2+泄漏度的降低.
主要成果:
- 1-5 wt%的生物炭显著改善了固化土壤的UCS,在这个范围内观察到最佳性能.
- 加入3.0%的生物炭将液压导电率降低到7.75 × 10-9 cm/s,孔径降低到43.12%.
- 生物炭的添加大大减少了Pb2+的漏,符合危险废物标准.
结论:
- 生物炭水泥复合材料增强了高Pb2+污染土壤的固化.
- 复合材料表现出提高的强度,降低的透性和有效的重金属固定.
- 这种技术为利用污染土壤作为次级填充剂提供了一种可行和有前途的方法.
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