关于石膏飞灰红色泥复合材料水泥糊填充后的应用和环境影响的研究
Zude Pan1, Rongxiang Pan1, Yang Cao2
1College of Chemistry and Chemical Engineering, Guizhou University, Guiyang, 550025, China.
Environmental science and pollution research international
|September 27, 2023
概括
这项研究使用红泥 (RM) 和波特兰水泥 (OPC) 开发了合石膏 (PG) 和飞灰 (FA) 混凝土糊补充剂 (CPB). 由此产生的材料具有出色的强度和耐水性,符合矿山填充标准,同时可以使废物有价值化.
科学领域:
- 材料科学 材料科学 材料科学
- 环境工程 环境工程
- 废物管理 废物管理
背景情况:
- 石膏 (PG) 和飞灰 (FA) 是工业副产品,需要可持续的处置解决方案.
- 开发有效的混凝土回填充 (CPB) 材料对于矿山安全和资源利用至关重要.
- 将PG,FA和红色泥 (RM) 等废弃物利用成功能性产品符合循环经济原则.
研究的目的:
- 调查使用石膏 (PG) 和飞灰 (FA) 作为主要成分的混凝土糊补充 (CPB) 的性能.
- 评估波特兰水泥 (OPC),红泥 (RM) 和烟 (SF) 对基于PG的CPB的性能的影响.
- 评估开发的CPB对矿山填充应用的环境影响和机械适用性.
主要方法:
- 使用不同比例的PG,FA,OPC,RM和SF准备CPB样本.
- 使用水/粘合剂比率和超塑性化剂 (SP) 含量来描述泥流动性.
- 在28天固化后,对机械性能 (强度) 和耐水性进行评估.
- 在浸泡过程中监测离子溶解 (Ca2+,SO42-),以了解水化机制.
- 微结构分析 (AFt,C-S-H) 和环境合规性的浸出试验.
主要成果:
- 在水/粘合剂比为0.2和0.7%的SP时,达到最佳的泥流动性.
- 28天后机械强度超过22MPa,满足了矿山填充要求.
- 增加的OPC,RM和SF含量显著提高了机械性能和耐水性.
- RM促进了持续的水合,这对于改善耐水性至关重要.
- 泄漏试验证实金属离子符合中国环境标准 (GB/T 14848-2017).
结论:
- 开发的基于PG-FA的CPB,由RM激活并与OPC结合,是矿山填充的可行且环保的材料.
- 这项技术有效利用工业废物 (PG,FA,RM),将其转化为高性能建筑材料.
- CPB具有出色的机械强度,耐用性和低环境影响,支持安全的采矿操作和废物资源回收.
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