226Ra从尾矿中的漏行为以及在地质技术介质中的吸附行为
Tian Xie1, Tuantuan Liu2, Bing Lian2
1China Institute for Radiation Protection, Taiyuan, Shanxi, 030006, China; College of Environmental Science and Engineering, Taiyuan University of Technology, Jinzhong, Shanxi, 030600, China.
Environmental pollution (Barking, Essex : 1987)
|May 3, 2024
概括
从尾矿中释放的-226 (Ra) 受水化学的影响. 控制pH和离子强度可以最大限度地减少Ra在地下水中的迁移,确保采矿现场的安全.
科学领域:
- 环境科学 环境科学
- 地质化学 地质化学
- 核科学 核科学 核科学
背景情况:
- 尾矿对环境构成风险,原因是放射性核素,如-226 (Ra) 的泄露.
- 了解水岩相互作用对于管理放射性废物和防止地下水污染至关重要.
研究的目的:
- 研究从尾矿中释放的226Ra的释放机制和迁移行为.
- 为了确定环境因素 (pH,固体-液体比,离子强度) 对Ra浸的影响.
- 评估Ra在地质层中的吸附和脱附特性.
主要方法:
- 对来自不同深度的尾矿样本中的Ra226存在状态的分析.
- 在各种条件下进行静态溶解浸出实验.
- 在具有代表性的地层学介质中对Ra的吸附-脱落的研究.
主要成果:
- 226Ra主要存在于尾矿中的残留和水溶性状态.
- 释放主要来自水溶性和可交换分数.
- 低pH,低固体-液体比,高离子强度有利于Ra的释放.
- Ra在层中表现出强烈的,可逆的吸附 (Kd: 1.07E+021.29E+03 mL/g).
结论:
- 尾尾物管理策略应侧重于控制pH值和离子强度,以限制Ra释放.
- 水障碍可以有效地减少Ra的迁移.
- 这些发现支持矿场的长期安全性和可持续性.
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