对于对anammox活性进行酸和自由酸抑制的个别评估
Koya Hirose1, Takashi Kondo2, Yayoi Saito2
1Graduate School of Science and Engineering, Toyo University, 2100 Kujirai, Kawagoe, Saitama 350-8585, Japan.
Journal of bioscience and bioengineering
|August 6, 2024
概括
高化物和自由酸 (FNA) 抑制了阿纳莫克斯细菌. FNA显示出比亚酸盐更大的抑制作用,IC50值约为0.7-0.88毫克L-1,对于优化anammox过程至关重要.
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
- 生物地质化学循环 生物地质化学循环
背景情况:
- 亚纳莫克斯 (无氧氨氧化) 过程对于废水处理中的去除至关重要.
- 高度的亚酸盐 (NO2−) 和自由酸 (FNA) 是已知的抑制剂的 anammox 细菌.
- 了解NO2-和FNA的明显抑制作用对于工艺的稳定性和效率至关重要.
研究的目的:
- 单独评估亚酸和自由酸对anammox细菌的抑制作用.
- 使用不同的生物质载体,比较NO2−与FNA的抑制功效.
- 为了确定稳定的anammox工艺应用的关键运行指标.
主要方法:
- 使用聚乙烯糖醇 (PEG) 凝和聚乙烯醇 (PVA) 载体与固定的anammox细菌进行了连续养测试.
- 在pH 7.6 (低FNA形成) 时评估了酸盐抑制.
- 在pH 6.4 (高FNA形成) 通过增加酸盐度来评估自由酸抑制.
主要成果:
- 化物抑制与NO2−度呈现线性关系 (PEG载体在350 mg N L−1下抑制13%).
- FNA抑制遵循西格曲线,50%的抑制度 (IC50) 为0.88毫克N L-1 (PEG) 和0.70毫克N L-1 (PVA).
- 与酸盐相比,FNA对anammox活性具有显著更大的抑制作用.
结论:
- 自由酸是一种比酸盐更强大的制剂,可以抑制anammox细菌.
- 对于NO2-和FNA的明显抑制机制和值对于操作控制至关重要.
- 这些发现提供了重要的指标,以确保在废水处理中稳定有效地应用anammox工艺.
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