使用EICP与石尾矿粉末相结合,改善了泥土土壤的冷解耐用性和环境风险评估
Hua Yuan1, Shuaiqi Wang1, Ziqi Zhu1
1School of Civil Engineering and Architecture, Henan University, Kaifeng, 475004, China.
Environmental research
|July 14, 2025
概括
酶诱导的碳酸盐沉与石矿尾矿改善了对结解周期的泥稳定性. 这种新的处理方法提高了土壤的强度,并减少了寒冷地区基础的环境风险.
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 是一种材料科学.
背景情况:
- 酶诱导碳酸盐沉 (EICP) 对土壤改善具有前景,但长期稳定性,特别是在冷解 (FT) 周期下,仍未得到充分研究.
- 季节性结地区的基础土壤因重复的FT周期而面临恶化,影响基础设施.
- 目前对EICP处理土壤的研究很大程度上忽视了在具有挑战性的环境中耐用性和性能.
研究的目的:
- 研究将EICP与矿尾矿 (MMT) 结合起来,以提高季节性结地区的泥稳定性的有效性.
- 评估重复的冷解周期对EICP-MMT处理的泥的机械性能,物理特性和微观结构的影响.
- 评估与处理土壤中的重金属漏相关的环境风险.
主要方法:
- 用酶诱导碳酸盐沉 (EICP) 与矿尾矿 (MMT) 结合处理了矿样本.
- 经过处理和未经处理的泥样本经过多次冷解 (FT) 周期,温度范围不同.
- 评估了机械性能 (不受限制的压力强度,切割模量),物理特性 (明显的多孔性,透性),微观结构和重金属漏.
主要成果:
- 在暴露于FT之前,EICP-MMT处理显著增加了未受限制的压力强度 (1.67x) 和切割模量 (3x),同时与未经处理的泥相比,明显的孔隙性 (20%) 和透性 (93%) 降低了.
- 经过FT循环后,EICP-MMT处理的污泥表现出优越的强度,性和刚性,表面孔隙度低于未经处理的污泥,尽管改善程度随着循环的增加而下降.
- 处理方法大大降低了重金属的漏和生物可用性,这表明环境污染风险较低.
结论:
- EICP-MMT处理提供了一种可行的策略,可以提高经过冷解周期的泥的耐用性和机械性能.
- 结合处理增强了土壤的稳定性,减少了环境风险,使其适合在季节性永久土地区的基础应用.
- 进一步的研究可以优化处理参数,以进一步减轻随着越来越多的冷-解周期而观察到的逐渐减少的改善.
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