作为补充水泥材料的不同生物质灰的比较评估:反应性,水化影响和环境考虑
Steffen Overmann1, Isabell Allwicher2, David Montag2
1Institute of Building Materials Research (ibac), RWTH Aachen University, Schinkelstr. 3, 52062 Aachen, Germany.
Materials (Basel, Switzerland)
|September 27, 2025
概括
生物质灰显示出作为可持续补充水泥材料 (SCM) 的潜力. 然而,它们的各种组成意味着性能不能被一般化,一些灰增强,而另一些灰阻碍了水泥的性能.
科学领域:
- 材料科学 材料科学 材料科学
- 土木工程 土木工程是指土木工程.
- 环境科学 环境科学
背景情况:
- 生物质灰被探索为煤炭飞灰的可持续替代品,用于补充水泥材料 (SCM) 应用.
- 生物质灰的多样性组成和特性阻碍了它们在水泥中的标准化使用.
- 了解灰成分和性能之间的关系对于它们的有效利用至关重要.
研究的目的:
- 调查各种生物质灰作为SCM的适用性.
- 评估不同灰的组成如何影响其在水泥系统中的性能.
- 评估与波特兰水泥混合灰的反应性,水化效应和强度的发展.
主要方法:
- 灰的表征 (木底灰,木灰,皮灰,污水污泥灰残留物) 包括环境参数.
- 使用R3测试和砂压力强度进行反应性测试.
- 在水泥混合物上使用异热热度计和X射线衍光度计 (XRD) 的水合研究.
主要成果:
- 木灰表现出低反应性 (R3热量<125 J/g SCM在7天内) 和损坏的砂强度 (在20%的替代下<0.6的相对强度).
- 皮灰 (249 J/g SCM) 和污水污泥灰残留物 (181 J/g SCM) 显示出显著的反应性,并有助于强度增加 (>0.85 在20%的替代下相对强度).
- 木灰对石水化有负面影响,而反应性灰主要消耗波特兰,但没有显著改变水化动力学.
结论:
- 生物质灰作为SCM的适用性高度依赖于原材料和燃烧条件,排除了一般化.
- 反应性灰,如皮灰和污水污泥灰残留物,在力量发展方面提供了可衡量的好处.
- 木灰,特别是灰,可以对水化和水泥强度产生负面影响,木底灰作为惰性填充剂.
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