在序列化批量膜气化生物膜反应器中,基于自由无氨酸酸的部分化
Lisheng Wang1, Xiaofeng Kang1, Yanchen Liu1
1State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China.
Water research
|June 8, 2023
概括
在膜气化生物膜反应器 (MABR) 中,使用自由氨 (FA) 和自由酸 (FNA) 控制策略实现了稳定的部分化. 这些方法有效地抑制了酸盐氧化细菌 (NOB),提高了去除效率.
科学领域:
- 环境工程 环境工程
- 微生物学 微生物学
- 废水处理 废水处理
背景情况:
- 膜气化生物膜反应器 (MABR) 提供节能去除,但由于独特的操作特性,实现稳定的部分化具有挑战性.
- 了解氧气转移,生物膜结构和微生物活动之间的相互作用对于优化MABR性能至关重要.
研究的目的:
- 提出和评估基于自由氨 (FA) 和自由酸 (FNA) 的控制策略,用于测序批次MABR的稳定部分化.
- 调查这些策略在不同低- (NH4+-N) 影响度下在延长运行期间的有效性.
主要方法:
- 经营了一批测序MABR超过500天,有控制的NH4+-N度.
- 实施了FA和FNA控制策略,以选择性地抑制酸盐氧化细菌 (NOB).
- 使用分子技术监测微生物社区的变化,以评估FA/FNA暴露的影响.
主要成果:
- 使用FA在~200 mg-N/L的影响下确定了部分化,抑制了NOB.
- 在较低的NH4+-N (~100 mg-N/L) 时,由低最终pH (<5.0) 生成的FNA对于NOB抑制是必要的.
- 暴露于FNA显著减少了94.6%的Nitrospira丰度,并增加了Nitrosospira丰度.
结论:
- FA和FNA是稳定MABR中部分化的有效策略,特别是在低NH4+-N度下.
- 无泡MABR需要更长的液压保留时间来产生足够的pH下降以产生有效的FNA度.
- 微生物群落的转变表明了针对NOB的抑制和氨氧化细菌 (AOB) 种群的潜在转变.
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