在低氧地下水过器中以pH为基础控制NH4+和Mn2+的氧化序列
Emiel Kruisdijk1, Francesc Corbera-Rubio2, Simon Müller2
1Delft University of Technology, Faculty of Civil Engineering and Geosciences, Department of Water Management, Stevinweg 1, 2628 CN Delft, the Netherlands; Eawag, Swiss Federal Institute of Aquatic Science and Technology, Ueberlandstrasse 133, CH-8600 Dübendorf, Switzerland.
Water research
|January 30, 2026
概括
这项研究通过分离 (Mn2+) 和 (NH4+) 氧化过程来控制地下水污染物的去除. 在过器中优化序列氧化,提高了处理效率和流量.
科学领域:
- 环境工程 环境工程
- 水处理技术水处理技术
- 地下水的修复 地下水的修复
背景情况:
- 无氧地下水通常含有铁 (Fe2+), (Mn2+) 和 (NH4+) 的污染物.
- 传统的快速砂过器使用同步的,不受控制的氧化还原反应来去除污染物.
- 相互关联的氧化过程使处理控制和效率复杂化.
研究的目的:
- 为了证明2+和NH4在地下水处理中的氧化过程的分离.
- 为了逆转典型的氧化序列,使Mn2+氧化在NH4+氧化之前.
- 为了研究工作条件 (O2度,pH) 对氧化途径和速度的影响.
主要方法:
- 在受控的低O2度和不同pH水平下对过器进行实验操作.
- 使用反应式运输建模进行参数估计.
- 分析Mn2+和NH4氧化之间的动力学和相互联系.
主要成果:
- 通过操纵O2水平和pH值来实现序列氧化:高pH值 (∼8) 在NH4+之前有利于Mn2+氧化,而低pH值 (∼6.8) 首先有利于NH4+氧化.
- 在没有NH4氧化的情况下,Mn2+的氧化速率明显更快 (大小的1个数量级).
- NH4+氧化似乎被同时的Mn2+氧化加速,观察到Mn2+在酸盐 (NO2-) 存在时释放.
结论:
- 将氧化过程分开成不同的过器提供了一个更容易控制的地下水处理系统.
- 优化个体氧化率 (Mn2+和NH4+) 可以提高处理效率,提高流量,减少反冲洗频率.
- 这些发现挑战了传统的治疗方法,因为它允许量身定制的顺序氧化以提高性能.
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