在部分脱-无氧氨氧化系统中,氧胺的双边作用和机制
Qi Zhang1, Lan Lin1, Yuqi Chen1
1Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, Xiamen University, Xiamen, Fujian, 361102, China.
Environmental research
|July 14, 2023
概括
氧胺 (NH2OH) 可以在部分脱和无氧氧化 (PD-anammox) 系统中促进去除. 然而,长期使用有缺点,但效果是可逆的,为PD-anammox应用提供了洞察力.
科学领域:
- 环境微生物学 环境微生物学
- 废水处理技术 废水处理技术
背景情况:
- 部分脱 (PD) 和无氧氨氧化 (anammox) 提供了一种新的去除方法.
- 优化脱剂和anammox细菌 (AnAOB) 之间的协同作用对于有效的PD-anammox性能至关重要.
研究的目的:
- 研究氧胺 (NH2OH) 对PD-anammox系统中的细菌活动,微生物能量流和功能微生物群协同作用的影响.
- 评估NH2OH促进或抑制去除的双边效应和潜在机制.
主要方法:
- 在PD-anammox反应堆中添加10mg/L的氧胺 (NH2OH).
- 监测去除率 (NRR) 和负载率 (NLR).
- 对代谢强度和途径的分析,以了解NH2OH的影响.
主要成果:
- NH2OH最初将NRR从0.05增加到0.30gN/L/d,NLR从0.10增加到0.40gN/L/d.
- 长期暴露于NH2OH导致完全脱的细菌过度生长,将NRR降低到0.11gN/L/d.
- 此外,NH2OH还增加了氧化 (N2O) 的排放和脱.
- 在停止NH2OH剂量后,抑制是可逆的,NRR恢复到0.27gN/L/d.
结论:
- NH2OH对PD-anammox系统具有双边作用,最初可以提高性能,但在长时间暴露后会导致抑制.
- 了解代谢机制是管理NH2OH影响的关键.
- 本研究为在PD-anammox过程中应用NH2OH提供了理论基础和技术参考.
相关概念视频
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