高飞灰含量的水化和硬化特性 凝材料用于水泥糊填充后利用
Bolin Xiao1,2, Jiandong Wang1,3, Aixiang Wu1,2,3
1State Key Laboratory of High-Efficient Mining and Safety of Metal Mine Ministry of Education, University of Science and Technology Beijing, Beijing 100083, China.
Gels (Basel, Switzerland)
|October 25, 2024
概括
一种新的飞灰粘合剂 (FCM) 提供了一种成本效益高且环保的替代品,可以替代普通波特兰水泥 (OPC) 在水泥填充 (CPB) 采矿中. 这种可持续的粘合剂可以将成本降低50%以上,同时满足矿山尾矿的强度要求.
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
- 可持续的采矿 可持续的采矿
背景情况:
- 在采矿业务中,越来越多地使用水泥回填充 (CPB) 方法.
- 迫切需要降低与传统粘合剂,如普通波特兰水泥 (OPC) 相关的成本和碳足迹.
研究的目的:
- 引入和评估一种使用低质量的F类飞灰 (FCM) 的新型回填凝粘合剂,作为OPC的可持续替代品.
- 为了研究液化,凝硬化特性和FCM在CPB中的适用性,在各种矿山尾矿中.
主要方法:
- 使用X射线衍射,入孔径测量,单轴压缩试验和热重力测量分析对粘合剂特性进行实验性调查.
- 使用三种不同类型的矿山尾矿验证FCM的适用性.
- 在强度,成本和水化特性方面对FCM-CPB与OPC-CPB进行比较分析.
主要成果:
- FCM-CPB的强度表现为OPC-CPB的72%,但不到生产成本的一半.
- FCM-CPB的水合过程经历了五个不同的阶段,产生了矿和凝状水合物.
- 与7天相比,FCM-CPB在28天显示出更高的多孔度 (31.2%),但平均毛孔尺寸较小,结构更密集.
- FCM表现出足够的强度,以满足各种矿山尾矿和采矿方法的要求.
结论:
- 拟议的基于飞灰的粘合剂 (FCM) 为CPB应用提供了可行的,经济的和对环境有益的OPC替代品.
- 通过可持续的回填解决方案,FCM有助于降低采矿业务的成本和碳足迹.
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