动态pH调节驱动Nitrosomonas进行高速稳定的酸性部分化
Siqi Li1, Xiaofeng Kang1, Zhiqiang Zuo2
1State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China.
Water research
|July 17, 2024
概括
在酸性环境中强化氨氧化率 (AOR) 是一个挑战. 这项研究引入了动态pH控制以提高AOR使用Nitrosomonas,实现90%以上的酸盐积累和高AOR而不抑制有益细菌.
科学领域:
- 环境微生物学环境微生物学
- 废水处理工程 废水处理工程
- 生物化学过程优化优化
背景情况:
- 氨氧化率 (AOR) 的强化对于酸性部分化技术至关重要.
- 在酸性条件下高水平的自由酸 (FNA) 抑制氨氧化细菌 (AOB).
- 现有的方法与FNA的AOB抑制作斗争,阻碍了工艺开发.
研究的目的:
- 提出和评估一个动态的酸性pH调节控制战略,用于高速酸性部分化.
- 研究动态pH对实验室规模反应堆中化细菌活动的长期影响.
- 为了实现高效的部分化,使用常见的AOB属Nitrosomonas.
主要方法:
- 在实验室规模测序批次移动床生物膜反应器 (SBMBBR) 中使用了700天.
- 实施了一种动态的酸性pH调节控制策略.
- 监测了流入的氨度,化物积累比率,AOR和FNA水平.
- 评估了FNA对酸盐氧化细菌 (NOB) 和AOB的无活化率.
主要成果:
- 达到超过90%的亚酸盐积累比率,影响NH4+-N度约为100 mg/L.
- 达到最大的AOR为14.5 ± 2.6毫克N L-1h-1.
- 证明了FNA在6.5毫克HNO2N/L有效地无活化NOB (无活化率0.61±0.08小时-1),而极小的影响Nitrosomonas (无活化率0.06±0.01小时-1).
- 废水的pH值保持在4.5,定期FNA达到足以使NOB无活化的水平.
结论:
- 动态酸性pH调节是高酸性部分化率的可行策略.
- 在动态酸性条件下,Nitrosomonas可以在受控的FNA暴露下有效地驱动部分化.
- 这种方法为稳定高效的酸性部分化提供了一条途径,克服了AOB抑制的挑战.
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