Zhou Bo, Niu Chengxin, Mao Wei, Wang Xueye, Wu Zhichao, Wang Zhiwei
State Key Laboratory of Water Pollution Control and Green Resource Recycling, Shanghai Institute of Pollution Control and Ecological Security, School of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China.
State Key Laboratory of Water Pollution Control and Green Resource Recycling, Shanghai Institute of Pollution Control and Ecological Security, School of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China.
Water Res. 2025 Oct 1;285:124080. doi: 10.1016/j.watres.2025.124080. Epub 2025 Jun 22.
This study investigated the effects of stepwise external voltages on an electrochemical anaerobic dynamic membrane bioreactor (EC-AnDMBR) for anaerobic digestion of waste activated sludge. Increasing the applied voltage greatly mitigated membrane fouling, reduced the transmembrane pressure increase rate and enhanced both volatile solids digestion and biogas production. The dynamic membrane structure became looser with fewer biofouling substances, attributed to a 42.6 % increase in the sludge-membrane interaction energy barrier at higher voltages. Electrochemical analysis revealed improved electroactivity of the anaerobic sludge, as evidenced by increased conductivity and reduced internal resistance. The proton-coupled electron transfer (PCET) pathway was promoted, indicated by a significant increase in the hydrogen/deuterium kinetic isotope effect from 616 to 25,990. Molecular simulations of dissolved organic matter (DOM) showed an enrichment of amide and quinone groups, along with stronger hydrogen-bonding and π-cation interactions, which may contribute to the PCET process. Moreover, elevated voltages promoted more deterministic microbial community assembly and reduced upstream microbial immigration. Gene upregulation in organic metabolism, electron/proton transport, and methanogenesis further supported enhanced digestion performance via PCET pathway. These findings offer valuable insights into the molecular mechanisms and microbial ecology of EC-AnDMBR systems, advancing the development of more efficient and sustainable sludge treatment technologies.
本研究考察了逐步施加外部电压对用于废活性污泥厌氧消化的电化学厌氧动态膜生物反应器（EC-AnDMBR）的影响。增加施加电压可极大减轻膜污染，降低跨膜压力上升速率，并提高挥发性固体消化率和沼气产量。动态膜结构变得更疏松，生物污染物质减少，这归因于较高电压下污泥 - 膜相互作用能垒增加了42.6%。电化学分析表明厌氧污泥的电活性得到改善，表现为电导率增加和内阻降低。质子耦合电子转移（PCET）途径得到促进，氢/氘动力学同位素效应从616显著增加到25,990表明了这一点。溶解有机物（DOM）的分子模拟显示酰胺和醌基团富集，同时氢键和π - 阳离子相互作用增强，这可能有助于PCET过程。此外，升高电压促进了更具确定性的微生物群落组装，并减少了上游微生物迁移。有机代谢、电子/质子运输和甲烷生成方面的基因上调进一步支持了通过PCET途径提高消化性能。这些发现为EC-AnDMBR系统的分子机制和微生物生态学提供了有价值的见解，推动了更高效、可持续的污泥处理技术的发展。
