用MSWI FA和在不同固化条件下的水泥凝固的疏沉积物的工程特性
Shucheng Zhang1, Haoqing Xu1, Xinmiao Shi2
1Jiangsu Province Engineering Research Center of Geoenvironmental Disaster Prevention and Remediation, School of Architecture and Civil Engineering, Jiangsu University of Science and Technology, Zhenjiang 212100, China.
Materials (Basel, Switzerland)
|June 13, 2025
概括
城市固体废物焚烧飞灰 (MSWI FA) 和普通波特兰水泥 (OPC) 复合固化疏沉积物 (DS) 提供了一个可持续的垃圾填埋场覆盖. 该材料符合有效填埋场覆盖的强度和耐久性要求.
科学领域:
- 地质技术工程 地质技术工程
- 材料科学 材料科学 材料科学
- 环境工程 环境工程
背景情况:
- 传统的填埋场覆盖材料表现出不充分的强度和干湿耐用性.
- 城市固体废物焚烧飞灰 (MSWI FA) 提出了一个处置挑战.
- 疏沉积物 (DS) 需要有效利用资源.
研究的目的:
- 调查使用MSWI FA和普通波特兰水泥 (OPC) 来固化DS用于填埋场覆盖应用的可行性.
- 评估复合材料的机械性能,透性和耐久性.
- 了解影响性能的微观机制.
主要方法:
- 复合材料制剂,含有不同的MSWI FA (0-60%) 和OPC (10-15%) 含量.
- 机械测试 (不受限制的压力强度) 和透性测试.
- 扫描电子显微镜 (SEM) 和X射线衍射 (XRD) 用于微观结构分析.
- 干湿周期耐用性测试. 干湿周期耐用性测试.
主要成果:
- 在28天固化后,以15%的OPC和20%的MSWI FA含量达到最佳性能.
- 不受限制的压力强度达到了1993.9kPa,符合垃圾填埋场覆盖标准.
- 透系数下降到<1×10−7cm/s,表明透率低.
- 鉴定出C-S-H凝,弗里德尔盐和埃特灵石是关键的强化和压缩阶段.
- 过多的湿度会对强度产生负面影响,这是由于可溶盐的水化和膨胀造成的.
结论:
- MSWI FA和OPC固化DS证明了垃圾填埋场中间覆盖系统的优异压缩性能.
- 该材料在定期的干湿周期下保持良好的工程性能.
- 这种方法为危险的MSWI FA处置和DS资源利用提供了双重解决方案,显示出显著的应用潜力.
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