投加微粉促进好氧颗粒污泥形成和稳定的机理研究

To data, the formation and stability of aerobic granules is strictly limited by operating modes which hindered its full-scale application. This study intends to adopt the way of adding micropowder to accelerating the formation and stability aerobic granulation. Both the micro-sized sludge powder and crystal powder are made from wastes. During the start-up phase of the reactor for treating waste water, adding waste powder is chosen to enhance the formation of aerobic granule. During the operating phase, in order to control the overgrowth of filamentous bacteria, micropowder is added to keep the stable structure of aerobic granules. The reactor operated under low organic loading conditions purposely to stimulate the overgrowth of filamentous bacteria, then increase the organic loading rates and add the micropowder simultaneously is another way for cultivating the big-size aerobic granules in a relatively short time. Biological morphology, molecular biology and hydromechanics methods will be used to analyze the mechanism of adding micropowder for accelerating the formation and stability of aerobic granules. The collaborative mechanism among micropowder as nuclei, extracellular polymerase substances as adhesion and filamentous bacteria as framework will be illuminated to reveal the inhibiting effect of filamentous bacteria on filaments and then the micropowder type, adding time, adding dosage and adding way of micropowder will all be determined. Aerobic granulation will be realized in reactors under low height to diameter conditions, low aeration rate and continuous flow respectively with the mechanism of waste powder for aerobic granulation and other auxiliary control measures which provide a feasible way and theoretical foundation for the application of aerobic granular sludge technology.

好氧颗粒污泥的形成和稳定依然受到苛刻的运行方式限制而使该技术未能广泛应用。本项目拟采用投加均为废弃物的微米级污泥微粉和水晶微粉方式，在污水处理反应器启动阶段，投加微粉快速形成好氧颗粒污泥；在运行阶段，投加微粉抑制丝状菌大量外伸生长以保持颗粒污泥的结构稳定；通过预先低有机负荷运行繁殖大量丝状菌后，突然加大负荷并投入微粉，促进较大粒径颗粒污泥的快速形成。采用生物形态学、分子生物学和流体力学分析投加微粉促进污泥颗粒形成和稳定的机理。阐明微粉作为凝聚核、胞外聚合物（EPS）作为粘合剂和丝状菌作为骨架之间的协同机制，揭示微粉对丝状菌的抑制作用原理，确定微粉种类、投加时机、投加量和投加方式。利用微粉促进污泥颗粒化原理和辅助的调控措施，在低高径比、低曝气量和连续流反应器中实现好氧污泥的颗粒化，为好氧颗粒污泥技术的应用提供一种可行的途径和理论依据。

好氧颗粒污泥是最有应用前途的污水生物处理技术之一。然而，好氧颗粒污泥形成和稳定依然受到苛刻的运行方式限制。本研究采用投加微米级污泥微粉、水晶微粉和改性污泥的方式，促进好氧颗粒污泥的快速形成和稳定性控制；投加微粉能抑制丝状菌大量外伸生长以保持颗粒污泥的结构稳定。进一步分析两种微粉的基本理化特性、成分和去向；考察微粉与生物以及EPS 之间的相互作用和粘结特性；研究微粉促进污泥颗粒化的效能、机理和构造模型；研究投加微粉对颗粒污泥的丝状菌控制的效能和机理；分析快速形成的颗粒污泥的特性和稳定程度。完成在低高径比、低曝气量SBR和连续流反应器中投加微粉加速好氧污泥的颗粒化和对丝状菌的控制。对投加微粉的机制和构造模型进一步剖析，探索了微粉尺度、释放碳源、丝状菌结构和EPS之间的集聚原理，研究了颗粒污泥的生物种群变化，为优化设计和运行提供了依据。