对在表面存储中遭受伤的水泥回填充处置的机械性能和微观结构演变的调查
Wenbin Xu1, Yalun Zhang1, Wei Chen1
1School of Energy and Mining Engineering, China University of Mining &Technology (Beijing), Beijing, 100083, PR China.
Journal of environmental management
|February 21, 2025
概括
在封闭的开放坑中处置表面凝糊 (SPD) 易受低温的影响. 袭击显著降低了SPD强度,但添加二氧化烟雾可以提高在寒冷地区的性能.
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
背景情况:
- 封闭的露天坑提供了一个可行的解决方案,用于储存尾矿,减轻环境污染和提高坑坡安全.
- 表面凝糊处理 (SPD) 由于其机械强度和低透性,有利于回填,但其性能取决于温度.
研究的目的:
- 调查袭击对SPD标本内部温度,机械性能和微观结构的影响.
- 评估二氧化烟雾 (SF) 作为部分水泥替代品在寒冷地区的有效性,用于SPD应用.
主要方法:
- 在不同的结温度,持续时间和发病时间下,对SPD标本进行了受控的实验室测试.
- 该研究分析了冷过程中的内部温度变化,机械强度 (UCS) 和微观结构演变.
主要成果:
- 早期SPD的冷过程涉及不同的冷却,冰核,快速结晶和最终结晶阶段.
- 袭击严重降低了SPD的压力强度,UCS在零下温度 (-1°C,-6°C,-12°C) 显著下降. 随着冷时间的延长和温度的降低,强度的损失会增加.
- 较晚的结开始允许SPD标本获得足够的强度来抵抗伤害. 烟添加,特别是5%的SF,在低温下提高UCS生长率.
结论:
- SPD的性能受到袭击的严重损害,因此在放置时需要仔细考虑环境温度.
- 优化结开始时间和结合二氧化烟雾是提高SPD在寒冷气候中的耐用性的关键策略.
- 这些发现为SPD伤损害机制提供了宝贵的见解,这对于在寒冷地区安全有效地管理尾矿至关重要.
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