来自中国东北地区的CaO飞灰固化泥的机械性能,耐久性性能和微观结构,中国
Chen Chen1,2, Kai Zhang3, Chunyu Ma4
1School of Civil Engineering, Institute of Disaster Prevention, Sanhe 065201, China.
Materials (Basel, Switzerland)
|October 16, 2024
概括
这项研究发现,增加氧化 (CaO) 和飞灰 (FA) 含量可以提高固化污泥的强度和耐用性. 结冰解和干湿循环降低了性能,强调了在寒冷的气候中需要有效的污泥处理.
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 材料科学 材料科学
背景情况:
- 泥固化对于废物管理和环境保护至关重要.
- 氧化 (CaO) 和飞灰 (FA) 是用于污泥稳定性的常见添加剂.
- 了解它们对机械性能和耐久性的影响对于实际应用至关重要.
研究的目的:
- 为了研究CaO和FA剂量和比例对固化污泥的影响.
- 评估凝固污泥的机械性能,耐用性和微观结构.
- 为了提供冷地区污泥处理的数据.
主要方法:
- 固化污泥样本以不同的CaO和FA含量进行准备.
- 使用冷-解 (F-T) 和干湿 (D-W) 周期来评估耐用性.
- 低场核磁共振 (LF-NMR) 用于分析微观结构.
- 测量了不受限制的压力强度 (UCS) 和直接剪切强度.
主要成果:
- 随着固化年龄和较高的CaO-FA比率,UCS和直接切割强度增加.
- 微观结构分析显示,随着固化,横向放松时间 (T2) 分布的变化.
- F-T和D-W周期导致UCS减少和孔隙恶化增加.
- 机械性能和微观结构受到CaO-FA含量和环境循环的显著影响.
结论:
- 优化CaO和FA含量可以提高固化污泥的性能.
- 泥的耐用性受到FT和DW周期的影响,特别是在寒冷的气候下.
- LF-NMR为固化和降解过程中的微观结构变化提供了宝贵的见解.
- 这些发现支持在具有挑战性的环境中有效的污泥管理策略.
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