解体好氧颗粒污泥的修复机理与过程强化研究

Aerobic granular technology has a great application prospect. While disintegration of aerobic granules are commonly observed during long-term operation and often lead to system failure. To ensure its industrial application, it is necessary to realize the rapid remediation of disintegrated aerobic granules. Preliminary study of the applicant has demonstrated the feasibility of adding floccular sludge for stimulating remediation of disintegrated granules. This project intends to further parse the interactions between floccular sludge and crushed granules, and to explore the remediation mechanisms and enhance the remediation processes. The remediation processes and key process parameters by adding different sources of floccular sludge will be firstly investigated. And during the remediation processes, we will attempt to parse the physicochemical and microbial interactions between floccular sludge and crushed granules through revealing the thermodynamic reasons and the role of extracellular polymeric substances (EPS), and identifying the key signaling molecules and microbial populations. After the relations among sludge thermodynamic properties, EPS, key signal molecules, and key microbial populations are established, the remediation mechanisms will be clarified. Further studies will be conducted on intensifying the remediation process and optimizing key process parameters. This project will provide the theoretical basis and technical support for promoting the full-scale application of aerobic granular technology.

好氧颗粒污泥工艺具有较好的应用前景，但在长期运行过程中常出现颗粒解体导致工艺失败的现象，实现解体好氧颗粒污泥快速修复是其工程化应用的重要保障。申请人的前期研究证实了投加污泥絮体修复解体颗粒碎片的可行性，本项目将基于修复过程中污泥絮体与颗粒碎片之间相互作用的解析，阐明解体好氧颗粒污泥的修复机理，并探索实现快速修复的过程强化策略。考察投加不同来源污泥絮体修复颗粒碎片的过程，探明关键工艺参数；揭示修复过程的热力学诱因和胞外聚合物(EPS)作用机制，识别关键信号分子和关键菌群，解析污泥絮体和颗粒碎片的物理化学和微生物相互作用；建立修复过程污泥热力学特性–EPS–关键信号分子–关键菌群之间的相互关系，阐明解体好氧颗粒污泥的修复机理；并开展修复过程强化与工艺参数优化研究，实现解体好氧颗粒污泥的快速修复。研究成果将为好氧颗粒污泥工艺的推广应用提供理论基础和技术支撑。

好氧颗粒污泥工艺具有显著的技术优势和广阔的应用前景，但长期运行过程中常出现颗粒解体导致工艺失稳或失效的情况，这是阻碍好氧颗粒污泥工艺大规模推广应用的主要技术瓶颈。研究解体好氧颗粒污泥修复机理，探索解体后颗粒污泥快速修复的过程强化策略及调控方法，对于推动好氧颗粒污泥工艺实际应用、维持工艺长期稳定运行至关重要。. 本项目研究了好氧颗粒污泥长达460天的长期运行过程中不同阶段（污泥驯化阶段、颗粒化阶段、成熟阶段和解体阶段）微观结构、理化特性、胞外聚合物（EPS）、N-酰基高丝氨酸内酯（AHLs）类信号分子和微生物群落等变化，对影响好氧颗粒污泥解体的因素进行综合研究，揭示了好氧颗粒污泥长期运行后的解体机制。结合零模型、斯隆中性模型、网络分析等方法探究了污泥颗粒化过程中微生物群落构建模式以及共现物种的生态机制，识别了促进污泥聚集的关键微生物菌群，明确了加强确定性过程强化关键菌群丰度和活性对于好氧颗粒污泥系统稳定运行的重要性。通过XDLVO理论分析、原子力显微镜观察等方法研究了好氧污泥颗粒化过程中细胞间的热力学相互作用，揭示了反应器内自身共存污泥絮体和颗粒污泥的热力学特性差异，证明了外源活性污泥絮体促进解体好氧颗粒污泥修复的重要性，探究了污泥絮体和颗粒碎片菌群相互作用机制，阐明了TB-EPS在促进解体好氧颗粒污泥修复中的作用。提出和验证了通过短期外源AHLs信号分子调控强化解体好氧颗粒污泥的结构修复和活性恢复的方法，揭示了外源AHLs信号分子在强化修复过程中的作用机制。. 本项目研究成果有助于丰富现有好氧颗粒污泥的基础理论，为好氧颗粒污泥工艺的大规模推广应用提供理论基础和技术支撑。