Key Laboratory of Groundwater Circulation and Environmental Evolution (China University of Geosciences (Beijing)), Ministry of Education, Beijing 100083, China; China University of Geosciences (Beijing), College of Water Resources and Environment, Beijing 100083, China.
Key Laboratory of Groundwater Circulation and Environmental Evolution (China University of Geosciences (Beijing)), Ministry of Education, Beijing 100083, China; China University of Geosciences (Beijing), College of Water Resources and Environment, Beijing 100083, China.
Waste Manag. 2018 Dec;82:177-187. doi: 10.1016/j.wasman.2018.10.028. Epub 2018 Oct 24.
Biologically treated landfill leachate (BTLL) is typically characterized by significantly high amount of total nitrogen (TN) and chemical oxygen demand (COD), and it has low biodegradability. In this study, a joint electrochemical system (JES) composed of iron anode reactor (IAR) and Ti/RuO anode reactor (TAR) was constructed to remove both TN and COD from BTLL and improve its biodegradability. The IAR and TAR with the same structure but using different anodes. As a result, JES could simultaneously remove COD and TN by 90.9 ± 0.3% and 90.2 ± 1.0%, respectively. Reduction of nitrite-N by Cu/Zn cathode in IAR and oxidation of ammonium-N by active chlorine in TAR were the major pathways for TN removal, while the COD could be removed by coagulation of iron flocs and oxidation by hydroxyl radicals and active chlorine. Fluorescence spectrum and parallel factor analysis showed that the main components of organics in BTLL were humic-like substances, fulvic-like substances, and soluble microbial degradation products. Humic-like substances were particularly removed by JES, and the remaining organics after electrolysis were some alkanes (e.g., heptane and nonane). Furthermore, decrease in molecular weight and aromaticity and increase in biodegradable substances indicated that the biodegradability of BTLL was effectively improved by the JES. The developed JES is a promising approach for application in the BTLL treatment.
经生物处理的垃圾渗滤液（BTLL）通常具有显著较高的总氮（TN）和化学需氧量（COD）含量，且可生物降解性低。本研究构建了由铁阳极反应器（IAR）和 Ti/RuO2 阳极反应器（TAR）组成的联合电化学系统（JES），用于去除 BTLL 中的 TN 和 COD，并提高其可生物降解性。IAR 和 TAR 具有相同的结构，但使用不同的阳极。结果，JES 可分别将 COD 和 TN 去除 90.9±0.3%和 90.2±1.0%。IAR 中 Cu/Zn 阴极还原亚硝酸盐-N 和 TAR 中活性氯氧化铵-N 是 TN 去除的主要途径，而 COD 可通过铁絮体的混凝和羟基自由基和活性氯的氧化去除。荧光光谱和平行因子分析表明，BTLL 中有机物的主要成分是腐殖质类物质、富里酸类物质和可溶微生物降解产物。JES 特别去除了腐殖质类物质，而电解后剩余的有机物为一些烷烃（如庚烷和壬烷）。此外，分子量和芳香度降低以及可生物降解物质增加表明 JES 有效提高了 BTLL 的可生物降解性。开发的 JES 是 BTLL 处理的一种很有前途的方法。
