College of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou 730050, PR China.
College of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou 730050, PR China.
Chemosphere. 2024 Apr;354:141741. doi: 10.1016/j.chemosphere.2024.141741. Epub 2024 Mar 16.
In this study, an aerobic granular sludge electrochemical system (AGES) was established by applying the micro-electric field to an aerobic granular sludge (AGS) reactor for the degradation of sulfamethoxazole (SMZ). Under the stimulation of the micro-electric field, the granulation of sludge was improved and the degradation rate of SMZ was enhanced. The features of granular sludge were characterized by scanning electron microscopy and X-ray diffraction. The optimal degradation rate of SMZ (88%) was obtained at the voltage of 3 V and the effective electrode area of 800 mm. The results of kinetics analyses revealed that the degradation of SMZ by AGES can be fitted with the second-order kinetic equation, showing a degradation rate constant (k) of 0.001 L mol·min. The degradation products of SMZ in the AGES system were detected by LC-MS and their possible degradation routes were elucidated. The micro-electric field in the AGES system played a selective role in microbes' enrichment and growth, changing the diversity of the microbial community. Pseudomonas, Tolumonas, and Acidovorax were the dominant bacteria in the AGES system, which is accountable for the abatement of SMZ and nutrients. This work provides a green means for improving AGS and paves the way for applying the AGS process to real-world wastewater treatment.
在这项研究中，通过向好氧颗粒污泥（AGS）反应器施加微电场，建立了好氧颗粒污泥电化学系统（AGES），用于降解磺胺甲恶唑（SMZ）。在微电场的刺激下，污泥的颗粒化得到改善，SMZ 的降解率得到提高。通过扫描电子显微镜和 X 射线衍射对颗粒污泥的特性进行了表征。在电压为 3 V 和有效电极面积为 800 mm 的条件下，SMZ 的最佳降解率（88%）。动力学分析结果表明，AGES 中 SMZ 的降解可用二级动力学方程拟合，表现出降解速率常数（k）为 0.001 L mol·min。通过 LC-MS 检测到 AGES 系统中 SMZ 的降解产物，并阐明了其可能的降解途径。AGES 系统中的微电场对微生物的富集和生长起到了选择性作用，改变了微生物群落的多样性。假单胞菌、托尔蒙纳菌和食酸菌是 AGES 系统中的优势菌，它们负责 SMZ 和营养物质的去除。这项工作为改善 AGS 提供了一种绿色手段，并为将 AGS 工艺应用于实际废水处理铺平了道路。
