通过真空预加载对填埋泥的冷持续时间的影响:EPS介导的脱水性,巩固性和微观结构演变
1Jiangsu Key Laboratory of Low Carbon and Sustainable Geotechnical Engineering, School of Transportation, Southeast University, Nanjing, Jiangsu Province, 211189, PR China.
Journal of environmental management
|February 21, 2026
概括
延长污泥结时间可以通过破坏细胞外聚合物质 (EPS) 来显著改善脱水和体积减小. 这提高了污泥的机械性能和巩固,有助于填埋污泥的管理.
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 是一种材料科学.
背景情况:
- 在全球范围内,填埋的污泥需要有效的排水和体积减少.
- 用真空预装冷是一种已建立的现场污泥处理方法.
- 有限的研究存在于结时间对污泥性能的影响.
研究的目的:
- 研究结时间和细胞外聚合物 (EPS) 对污泥脱水性,机械性质和微观结构变化的影响.
- 为了确定最佳的冷时间,加强污泥处理.
- 为有效地管理填埋污泥提供指导.
主要方法:
- 泥样本经过不同时间的冷.
- 测量包括特定的过阻力 (SRF),毛细管吸收时间 (CST),空隙比,压缩指数,巩固系数和液压导电.
- 分析了细胞外聚合物物质 (EPS) 分数 (LB-EPS,S-EPS).
- 微结构分析侧重于粒子大小和孔隙分布.
- 量化了体积减小和水含量.
主要成果:
- 增加结时间显著减少了SRF和CST,改善了脱水能力.
- 较长时间的冷破坏了EPS,特别是松结合 (LB-EPS) 和可溶性 (S-EPS) 分数.
- 结增强了巩固特性,使巩固系数和液压导电率增加了1-2个数量级.
- 96小时的冷时间实现了54.9%的体积减少,并将含水量从86%降低到57.3%.
- 长时间的冷导致了更大的颗粒大小和更大的中孔/宏孔丰度,创造了更密集的污泥结构.
- EPS含量与可压缩性,巩固性,脱水性和微观结构变化有很强的相关性.
结论:
- 延长结时间是提高污泥脱水和凝固的关键因素.
- EPS 干扰是改善污泥工程性能的一个关键机制.
- 这项研究为优化现场处理垃圾填埋泥通过控制冷时间提供了重要的见解.
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