Ouyang Boda, Zhang Zhiyong, Chen Fuzhi, Li Fei, Fu Ming-Lai, Lan Huachun, Yuan Baoling
Xiamen Key Laboratory of Municipal and Industrial Solid Waste Utilization and Pollution Control, College of Civil Engineering, Huaqiao University, Xiamen, Fujian 361021, PR China.
Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China.
Water Res. 2025 Apr 1;273:123024. doi: 10.1016/j.watres.2024.123024. Epub 2024 Dec 21.
As freshwater demand grows globally, using reclaimed water in natural water bodies has become essential. Constructed wetlands (CWs) are widely used for advanced wastewater treatment due to their environmental benefits. However, low carbon/nitrogen (C/N) ratios in wastewater limit nitrogen removal, often leading to eutrophication. This study explores the use of sewage sludge biochar (SB) and activated carbon (AC) as electrodes in microbial fuel cell-constructed wetlands (MFC-CW) to enhance nitrogen removal and energy generation. Results indicated that the sludge biochar closed-circuit CW (MSBS-CW) achieved considerable total nitrogen removal (95.85 %) and maximum power density (9.05 mW/m²). Furthermore, high-throughput sequencing and functional gene analysis revealed substantial shifts in the microbial community within MSBS-CW, particularly in the electroactive bacteria (Geobacter), autotrophic denitrifying bacterium (Hydrogenophaga, Thiobacillus) and anaerobic ammonium oxidation bacteria (Candidatus_Brocadia). Electrochemical and material characterization showed that SB enhanced the cathode's electrochemical performance and the anode's biocompatibility, thereby improving denitrification and energy generation. This study demonstrates that sludge biochar is an effective low-cost electrode material for MFC-CW systems, offering a sustainable solution for nitrogen removal and energy production under carbon-constrained conditions.
随着全球淡水需求的增长，在天然水体中使用再生水变得至关重要。人工湿地（CWs）因其环境效益而被广泛用于深度废水处理。然而，废水中低碳/氮（C/N）比限制了氮的去除，常常导致富营养化。本研究探索了将污水污泥生物炭（SB）和活性炭（AC）用作微生物燃料电池-人工湿地（MFC-CW）中的电极，以提高氮去除率和发电量。结果表明，污泥生物炭闭路人工湿地（MSBS-CW）实现了可观的总氮去除率（95.85%）和最大功率密度（9.05 mW/m²）。此外，高通量测序和功能基因分析揭示了MSBS-CW内微生物群落的显著变化，特别是在电活性细菌（地杆菌属）、自养反硝化细菌（嗜氢菌属、硫杆菌属）和厌氧氨氧化细菌（“Candidatus_Brocadia”）方面。电化学和材料表征表明，SB增强了阴极的电化学性能和阳极的生物相容性，从而改善了反硝化作用和发电量。本研究表明，污泥生物炭是MFC-CW系统一种有效的低成本电极材料，为碳受限条件下的氮去除和能源生产提供了可持续的解决方案。
