College of Marine Ecology and Environment, Engineering Research Center for Water Environment Ecology in Shanghai, Shanghai Ocean University, Hucheng Ring Road 999, Office B207, Pudong District, Shanghai, 201306, China.
State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai, 201620, China.
Microb Ecol. 2022 Feb;83(2):340-352. doi: 10.1007/s00248-021-01752-5. Epub 2021 Jun 4.
Wastewater recycling can alleviate the shortage of water resources. Saline water is seldom treated with biological processes, and its recycling rate is low. Constructed wetland (CW) is a safe, economical, and ecological water treatment method. However, the saline water treatment performance of CW is not good. Microbial desalination cells (MDC) utilizing a bioelectrochemical approach achieve functions of desalination and power generation. In this study, MDC was used to strengthen CW to form a composite system, MDC-CW. Through optimization of design parameters, MDC-CW was applied in the treatment of salt-containing water. The average total nitrogen removal rate in MDC-CW-P1 reached 87.33% and the average COD removal rate was 92.79%. The average desalination rate of MDC-CW-P1 was 55.78% and the average voltage of MDC-CW-P1 reached 0.40 mV. Planting Canna indica in the MDC-CW was conducive to the functions of desalination and power generation. The above results were also verified by the microbial analysis results of gravels in the substrate, plant rhizosphere, and electrodes. In addition, the decontamination of the device mainly depended on the function of the bacteria commonly used in water treatment, such as Proteobacteria and Bacteroidetes, whereas the generation of power depended on the function of Geobacter. Salt ions moved spontaneously to the cathode and anode under the influence of current generation so that the desalination function was realized under the selective isolation function of exchange membranes. The device design and laboratory applications of MDC-CW experimentally achieved the electrochemical function and broadened the treatment scale of CW.
污水再生可以缓解水资源短缺问题。咸水很少采用生物处理，其循环利用率低。人工湿地（CW）是一种安全、经济、生态的水处理方法。但是，CW 处理咸水的效果不佳。微生物脱盐电池（MDC）利用生物电化学方法实现脱盐和发电功能。本研究采用 MDC 强化 CW 形成复合系统，即 MDC-CW。通过优化设计参数，将 MDC-CW 应用于含盐废水处理。在 MDC-CW-P1 中，总氮去除率平均达到 87.33%，COD 去除率平均达到 92.79%。MDC-CW-P1 的平均脱盐率为 55.78%，平均电压达到 0.40 mV。在 MDC-CW 中种植美人蕉有利于脱盐和发电功能。以上结果还通过基质砾石、植物根际和电极微生物分析结果得到验证。此外，该设备的去污主要依赖于水处理中常用细菌的功能，如变形菌门和拟杆菌门，而发电则依赖于地杆菌的功能。在电流产生的影响下，盐离子自发地向阴极和阳极移动，从而在交换膜的选择性隔离功能下实现脱盐功能。MDC-CW 的装置设计和实验室应用在电化学功能方面进行了实验，扩大了 CW 的处理规模。
