来自飞灰碳化物渣的高性能C-A-S-H种子,用于激活渣向低碳结合剂
Xingang Wang1, Yong Yu1, Fubing Zou1
1School of Infrastructure Engineering, Nanchang University, Nanchang 330031, China.
Journal of environmental management
|July 31, 2023
概括
高性能氧化酸盐水合物 (C-A-S-H) 纳米种子是从废物如飞灰和碳化渣中合成的. 这些种子显著增强了渣水泥的性能.
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:
- 补充性水泥材料 (SCM) 对可持续混凝土至关重要.
- 渣 (LS) 是一个有前途的SCM,但它的激活需要高效的方法.
- 像飞灰 (FA) 和碳化碳渣 (CS) 这样的废物材料为开发新型水泥添加剂提供了机会.
研究的目的:
- 从FA和CS中开发高性能氧化酸盐水合物 (C-A-S-H) 种子的一步合成方法.
- 为了研究这些C-A-S-H种子对LS水泥性能的影响.
- 探索利用废物材料用于先进的SCM的潜力.
主要方法:
- 机械化学混合FA和CS7天,合成C-A-S-H种子.
- 将C-A-S-H纳米种子 (重量1.0%) 纳入用聚碳酸超塑化剂 (PCE) 的LS水泥砂中.
- 通过电流测量,对1日和28天后的砂压力强度和化物抵抗的评估.
主要成果:
- 合成的C-A-S-H种子的Ca/Si比为1.5,显示出最佳的性能.
- 添加1.0%的C-A-S-H纳米种子 (Ca/Si=1.5) 增加了1天和28天的砂压力强度分别为67%和29%.
- LS水泥的抗性得到了显著的改善,电流减少了30%以上.
结论:
- 从废物中单步机械化学合成C-A-S-H种子是可行的和有效的.
- 优化的C-A-S-H种子 (高Ca/Si,特定形态) 提高LS水泥性能,包括强度和耐用性.
- 这种方法提供了一种可持续且具有成本效益的方法,用于在水泥应用中利用工业废物.
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