揭示了氨氧化过程和使用和氧同位素分离效应的快捷化性能
Hong Liu1, Wei Zeng1, Mengjia Zhan1
1National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Department of Environmental Engineering, Beijing University of Technology, Beijing 100124, China.
The Science of the total environment
|December 16, 2023
概括
在快捷化中研究和氧同位素分离的研究显示,温度显著影响同位素,而溶解的氧则影响氧同位素. 这种双同位素技术有效地监测废水中的生物去除过程.
科学领域:
- 环境科学 环境科学
- 环境化学环境化学
- 生物地质化学生物地质化学
背景情况:
- 从废水中去除生物对于环境保护至关重要.
- 同位素分离是理解变化的强大工具.
- 捷径化是一种高效的生物去除过程.
研究的目的:
- 分析 (N) 和氧 (O) 元素在使用双同位素分离的快捷化过程中的迁移和转变.
- 调查溶解氧 (DO) 和温度对捷径化性能和同位素分离的影响.
- 用同位素标记物阐明快捷路径化机制.
主要方法:
- 使用N和O双同位素分离技术.
- 调整了溶解氧度 (0.2-0.4,1-1.2和3-4毫克/升).
- 温度的变化 (18±1°C,25±1°C和33±1°C).
- 采用了18O标记的H2O追踪器实验.
主要成果:
- 无论是δ15N-NO2和δ18O-NO2都随着NO2-N的积累而增加.
- 温度的分成效比DO更大.
- 较高的温度增加了δ15N-NO2;较高的DO增加了δ18O-NO2.
- 100%的18O从H2O转移到NO2--N证实了同时的DO和H2O参与.
结论:
- 双同位素分离有效地揭示了捷径化性能和机制.
- 在这个过程中,温度和DO是影响N和O同位素分离的关键因素.
- 这些发现为优化废水处理中的生物去除提供了洞察力.
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