基于群体感应效应的化学解偶联剂污泥减量过程与调控研究

The biological treatment of wastewater produces large amounts of excess sludge. Up to now, the treatment and disposal of excess sludge has become an important environmental issue for worldwide. The object of the project was to increase the efficiency of sludge reduction in the biologcial wastewater treatment by chemical uncoupler based on quorum sensing. Combination of batch and continuous tests, the changes of quorum sensing in the sludge reduction process by chemical uncoupler are studied with chemistry, cell biology and microbiology analysis. The relationship between quorum sensing and sludge reduction by chemical uncoupler are explain clearly. In order to reveal the reasons and mechanisms for lower of wastewater treatment efficiency and change of sludge characteristics, the effecting processes and mechanisms of chemical uncoupler on sludge and its microorganism in the process of sludge reduction are investigated.The synergies and relationships between quorum sensing signal molecules and chemical uncoupler are discussed. In order to finding safer and more efficient ones, the screen of chemical uncouper based on quorum sensing are studied. To optimize the sludge reduction process, the regulation and its mechanism of sludge reduction by chemical uncoupler based on quorum sensing are discussed. The study could provide a theoretical basis and technical guidance for the source reduction of sludge technology in biological wastewater treatment process by dosing quaternary phosphonium compound and promote the development and application of this technology.

污水的生物处理会产生大量剩余污泥，剩余污泥的处理处置已成为人们关注的重要环境问题。针对目前污泥现状和化学解偶联剂污泥减量技术存在的不足，本项目以提高污泥减量效果为目标，开展基于群体感应的化学解偶联剂污泥减量过程与机制研究。通过批量试验和连续试验，结合化学、微生物学和细胞生物学等分析方法，考察群体感应效应在化学解偶联剂污泥减量过程中的作用及变化，阐明群体感应与化学解偶联剂减量污泥的关系；研究污泥减量过程中化学解偶联剂对污泥及其微生物的作用过程和机制，揭示污水处理效果降低与污泥特性变化产生原因和机制；研究污泥减量过程中群体感应信号分子与解偶联剂的协同作用及关系，探讨基于群体感应化学解偶联剂的筛选，筛选更安全、有效的化学解偶联剂；分析基于群体感应效应化学解偶联剂污泥减量的调控及机理，为污水处理过程中化学解偶联剂污泥减量技术及其应用提供理论依据和技术指导，推动这种污泥减量技术的应用和发展。

针对目前污水处理过程中污泥产量大和化学解偶联剂污泥减量技术存在的不足，研究了3种化学解偶联剂添加对在连续运行污水处理过程中污泥减量、污水处理效果、污泥性质等影响。发现3种化学解偶联剂的污泥减量机制不完全相同。化学解偶联剂会导致污水处理效果有一定下降、污泥更容易发生膨胀、污泥沉降性能变差，易发生反絮凝作用。比较了2种不同工艺（A2O和SBR）中化学解偶联污泥减量的效果，发现化学解偶联剂在这2种工艺中均会导致污泥减量，污泥减量效果差不多。深入研究表明，化学解偶联剂是通过影响污泥微生物代谢和微生物菌群结构，一方面增加污泥EPS尤其是其中碳水化合物，另一方面减少产群体感应信号分子的微生物、增加萃灭群体感应信号分子的微生物。结合文献和污泥特性，建立了活性污泥中群体感应信号分子的指示菌定性法、指示菌半定量法和高效液相串联二级质谱的定量分析方法。半定量和定量分析表明化学解偶联剂的添加会降低污泥的群体感应信号分子-AHLs量，而群体感应信号分子的减少反过来影响污泥的各种特性，如粒径、絮体强度、絮体微生物粘附力和污泥沉降性能等，导致污泥絮体变得松散，导致污泥更容易发生膨胀，最终影响污水处理效果。外源性群体感应信号分子的添加可以补偿化学解偶联剂减少的群体感应信号分子，使污泥特性得到了改善，污泥易膨胀性下降，污水处理效果变好。研究发现不同位置添加化学解偶联剂对污泥化学解偶联污泥减量的效果影响不大，而化学解偶联剂的添加量对污泥量效果有较大影响，确定了3种化学解偶联剂的最佳添加量。通过化学解偶联剂的降解、生态毒性和成本分析，发现THPS为更安全可靠、更绿色环境友好和更价廉的化学解偶联剂。这些研究结果可以为污水处理过程中化学解偶联剂污泥减量技术及其应用提供理论依据和技术指导，推动这种污泥减量技术的应用和发展。