生物电催化耦合膜分离强化甲醇废水厌氧处理及调控机制

The anaerobic granular sludge disintegration, rupture and washing-out are the key factors that restrict the real application of the upflow anaerobic sludge blanket (UASB) in the treatment of methanolic wastewater. The objective of this research is to develop a new up-flow anaerobic process by coupling bioelectrocatalytic and membrane separation technologies into UASB system to retain microorganisms through membrane filtration and to diversify the microbial populations and promote the re-granulation of dispersed granules via bioelectrocatalytic regulation. The molecular biology methods will be used to analyze the enrichment, evolution, and adhesion behaviors of electroactive microorganisms in the fermentation liquid phase and the electrode interface to elucidate the syntrophic interactions and electron transfer mechanisms of the different functional microbes, and the potential strengthening effect on the re-granulation of dispersed granules. The operational process will be optimized and assessed by multi-factor analysis, and the chemical compositions, three-dimensional configuration, microbial cell morphology and other microscopic changes of the granules and the membrane foulants overtime will be characterized to explore the synergistic molecular mechanisms of bioelectrocatalytic process in electrically regulating the re-granulation of dispersed granules and membrane pollution control. The current research will provide the basic theory for developing a cost-efficient hybrid bioelectrocatalytic membrane process for the safe treatment of methanolic wastewater while simultaneously maximizing energy recovery.

厌氧颗粒污泥细化、破裂与流失是制约上流式厌氧污泥床（UASB）处理甲醇废水的关键因素。本研究拟以上流式厌氧污泥床为主体，引入生物电催化耦合膜分离技术，通过膜过滤原位截留微生物，实现微生物停留时间和水力停留时间的分离，借助生物电催化微电流调控，丰富微生物种群多样性，促进细化污泥的再颗粒化与多元化。在此基础上，借助先端分子生物学手段，解析发酵液相、电极界面电活性微生物膜的富集与粘附规律及种间协作关系，阐明功能菌电子释放和传递机制，明确微生物电催化在细化污泥再颗粒化的诱导强化效应；通过多因素分析优化反应运行效率，借助共聚焦扫描显微镜等手段，识别时间尺度下膜面污染物的化学构造与三维构型、微生物细胞形态等微观变化规律，阐明生物电催化在膜污染防控的协同增效分子机制。通过本研究的开展，预期完善生物电催化耦合膜分离强化甲醇废水厌氧能源化处理及调控理论体系，为甲醇废水安全处置和最大化能源回收提供技术参考。

厌氧颗粒污泥细化、破裂与流失是制约上流式厌氧污泥床（UASB）处理甲醇废水的关键因素。本项目以上流式厌氧污泥床为主体，引入生物电催化耦合膜分离技术，通过膜过滤原位截留微生物，实现微生物停留时间和水力停留时间的分离。借助生物电催化微电流调控，丰富微生物种群多样性，促进细化污泥的再颗粒化与多元化。通过先端分子生物学手段，解析发酵液相、电极界面电活性微生物膜的富集与粘附规律，明确了生物电催化在膜生物处理中细化污泥再颗粒化的诱导调控与强化效应；通过共聚焦扫描显微镜等手段进行多因素分析优化反应运行效率，解析了时空尺度下膜面污染物的化学构造与三维构型、絮体结构、微生物细胞形态等微观变化规律，阐明生物电催化系统在膜污染防控的协同增效机制。通过一系列研究的开展，本项目形成了基于微生物电催化诱导的组合式甲醇废水的高效厌氧能源化集成技术。将生物电催化与上流式厌氧污泥床耦合处理3000 mg/L的甲醇废水在0.8 V下，甲烷产量达388.0 mL/L-reactor/d以及CO2产量较未加电的UASB低52.8%。粒径大于300 µm的颗粒污泥占比从最初的1.3%增加至22.4%。同时组建了生物电催化耦合膜生物反应器（BES-AnMBR），在OLR 20.00 g-COD/L/d条件下，系统比较了不同电压调控下对甲醇废水处理效果和污泥再颗粒化的影响，发现最佳电压为0.6 V，可提高AnMBR对甲醇废水的处理效率（96%-98%），CH4产量高达5.39 L-CH4/L-reactor/d，微电流刺激使污泥的中位粒径从未加电时的16.39 μm增大到30.18 μm，缓解了长期运行过程中的污泥颗粒细化现象。本研究完善了生物电催化耦合膜分离强化甲醇废水厌氧能源化处理及调控理论体系，为甲醇废水安全处置和最大化能源回收提供技术参考，也为传统膜生物反应器理论体系提供了科学依据和指导。