用活性化水泥材料在矿加工残留物固化/稳定中的制备和应用
Pengyue Su1, Pan Zhao1, Hao Wang1
1School of Environmental and Chemical Engineering, Jiangsu Ocean University Lianyungang 222005 China xiaming@jou.edu.cn.
RSC advances
|June 21, 2024
概括
矿加工残留物 (COPR) 用高炉渣和飞灰制成的活性化水泥材料 (AACM) 成功固化. 这种方法有效地固定了危险的,满足了处置标准并保持了机械强度.
科学领域:
- 环境科学 环境科学
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 矿加工残留物 (COPR) 是一种含有有毒Cr6的危险废物.
- 对于COPR来说,它带来了相当大的生态和人类健康风险.
- 有效的废物管理策略对于环境保护至关重要.
研究的目的:
- 使用活性化水泥材料 (AACM) 调查COPR的固化/稳定 (S/S).
- 为了优化AACM属性,以便有效地固定.
- 评估含有COPR的AACM的机械性能和浸出行为.
主要方法:
- 使用高炉渣 (BFS) 和飞灰 (FA) 制备AACM.
- 单因素实验以确定最佳参数 (水玻璃模量,液体-固体比,-固体含量,固化温度).
- 压力强度测试,Cr (VI) 和总Cr浸测试,XRD,FTIR和SEM分析.
主要成果:
- 在最佳条件下,压力强度为147.6 MPa.
- 使用60%的COPR添加的AACM保持了38.2MPa的压力强度.
- 的化 (VI) 和总满足了AACM的处置限制,其中50%是COPR.
- XRD,FTIR和SEM证实了通过物理和化学手段的固定.
结论:
- AACM是COPR的S/S的一个有效材料.
- 优化的AACM显示出出色的机械性能,并大大减少了的出水.
- 凝固的COPR适用于建筑和垃圾填埋,减轻环境风险.
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