基矿物相转化铁矿石尾矿的水化和性能,作为补充的固材料
Zhidong Tang1, Xiangheng Meng1, Yuexin Han1
1School of Resources and Civil Engineering, Northeastern University, Shenyang, 110819, China; National-local Joint Engineering Research Center of High-efficient Exploitation Technology for Refractory Iron Ore Resources, Shenyang, 110819, China.
Journal of environmental management
|March 19, 2024
概括
这项研究表明,热处理的铁矿石尾矿 (HMPT-IOT) 具有潜在的液压和波佐兰性质,使其能够在混凝土应用中用作补充水泥材料 (SCM).
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.
- 地质化学 地质化学
背景情况:
- 铁矿石尾矿 (IOT) 通常需要激活才能作为补充性水泥材料 (SCM),这限制了它们在建筑中的广泛使用.
- 研究激活IOT的新方法对于可持续的建筑材料开发至关重要.
研究的目的:
- 探索热处理铁矿石尾矿 (HMPT-IOTs) 的潜在液压和波佐兰特性.
- 综合评估HMPT-IOT作为SCM对水泥材料机械性能,水化,微观结构和孔状结构的影响.
主要方法:
- 机械测试 (压力强度)
- 液化热试验 液化热试验
- 在X射线衍射 (XRD) 中.
- 扫描电子显微镜 (SEM) 的使用
- 热重力测量分析 (TG)
- 入孔径测试 (MIP) 是一种入孔径测试.
主要成果:
- 在10%,20%和30%的水泥替代HMPT-IOT的28天压力强度分别为41.9 MPa,47.9 MPa和37.5 MPa.
- 30%的替代减少了累积的加水热,促进了早期的加水,并导致更密集的微观结构与相互连接的加水产品.
- 在28天后,Ca (OH) 2的消耗量达到约2%,毛孔总体量略有增加,但微毛孔和过渡毛孔减少.
结论:
- 由于其固有的液压和pozzolanic活动,HMPT-IOT显示出作为SCM的巨大潜力.
- 优化HMPT-IOT的替代水平可以提高具体的性能,包括强度和微观结构.
- 这项研究为可持续建筑材料中铁矿石尾矿的价值化提供了一条途径.
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