低营养低剪切条件下厌氧颗粒污泥形成的群感机理及调控

Anaerobic sludge granulation was observed in carrier anaerobic baffled reactor (CABR) at low nutrition and low shear. The mechanisms of anaerobic sludge granulation are investigated with quorum sensing theory. Based on the solution to extraction and detection of signal molecules in anaerobic granular sludge reactor, key signal molecules, which contribute to anaerobic sludge granulation, are identified through setting control. Besides, the inner relationships among external stress, signal molecular secretion and sludge granulation are ascertained, through reviewing morphology, physical property, chemical constitution and microorganism space-time distribution characteristics of anaerobic granular sludge. Induction of signal molecular for anaerobic sludge granulation is confirmed through dosing the key molecular signals and quorum sensing inhibitors/signal degradation enzymes. At the same time, the feasibility of regulation strategy with quorum sensing for anaerobic sludge granulation is affirmed. The study is benefit for us to understand and proclaim the mechanisms of anaerobic sludge granulation at low nutrition and low shear. Moreover, it is of important significance to carry out the project for enhancing efficiency and stability of anaerobic bioreactor, and improve the foundation theory and technology in our wastewater biotreatment field.

针对课题组开发的填料式折流板反应器（CABR）在低营养低剪切条件下可实现厌氧污泥颗粒化的现象，本项目拟从群体感应（Quorum Sensing, QS）角度探查厌氧颗粒污泥的形成机理。在建立厌氧颗粒污泥体系信号分子富集和检测方法的基础上，通过设置对照组，识别低营养低剪切条件下厌氧污泥颗粒化过程中关键信号分子，结合颗粒污泥的形态学特征、物理特性、化学组成以及微生物种群的时空分布，探明环境压力-信号分子-污泥颗粒化之间的内在关系；通过投加关键信号分子以及关键信号分子的抑制剂或降解酶，验证信号分子对厌氧颗粒污泥的诱导作用机理及强化调控策略的可行性，这有助于我们更好的理解和阐明低营养低剪切条件下厌氧颗粒污泥的形成机理。项目的实施对于提高厌氧反应器高效性和稳定性，提升我国在废水生物处理的基础理论和工艺领域的研究水平将具有十分重要的意义。

厌氧颗粒污泥由于其较长的颗粒污泥培养周期及复杂的颗粒化机理已成为国内外废水生物处理领域的一个重要研究方向。本研究项目通过调查3种典型工业废水处理厂的厌氧颗粒污泥，探明关键信号分子在水相、水洗相及泥相中的分布比例，并根据信号分子自身的物理化学特性分析其在不同pH、有机负荷冲击及氮供应失衡条件下信号分子与厌氧颗粒污泥的相互关系及作用规律，结合上述群体感应规律设计群感调控器，加速低营养低剪切条件下厌氧污泥的颗粒化进程，为厌氧颗粒污泥的培养技术提供新思路。研究发现，厌氧颗粒污泥中DSF主要分布于泥相，而AI-2却集中于水相，至于AHLs的分布与其分子结构中的酰基链长度和取代基相关，并根据信号分子的分布情况明确各类信号分子对厌氧颗粒污泥内外层EPS合成的作用规律。通过改变pH、有机负荷及氮供应条件，发现不同信号分子的生态行为在厌氧颗粒污泥各相污泥特性退化中的作用，从而确定信号分子的最佳作用环境。在群体感应调控器的促进下，污泥的颗粒化进程明显加快，污泥的颗粒化特性显著优于对照实验组。已发表期刊论文10篇；已有1项中国发明专利被授权。