Gholizadeh Abdolmajid, Ebrahimi Ali Asghar, Salmani Mohammad Hossein, Ehrampoush Mohammad Hassan
Environmental Science and Technology Research Center, Department of Environmental Health Engineering, Shahid Sadoughi University of Medical Sciences, Yazd, Iran; Esfarayen Faculty of Medical Sciences, Esfarayen, Iran.
Environmental Science and Technology Research Center, Department of Environmental Health Engineering, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
Chemosphere. 2017 Dec;188:470-477. doi: 10.1016/j.chemosphere.2017.09.009. Epub 2017 Sep 4.
Microbial desalination cell (MDC) is a new approach of water desalination methods, which is based on ionic species removal from water in proportion to the electric current generated by bacteria. However, the low current generation and insufficient deionization in this technology have created challenges to improve the process. Here, the performance of MDC using ozone as a new electron acceptor (O-MDC) was evaluated versus another operated independently with oxygen (O-MDC). Results showed the maximum open-circuit voltages of 628 and 1331 mV for 20 g L NaCl desalination in O-MDC and O-MDC, respectively. The O-MDC produced a maximum power density of 4.06 W m (about 11 times higher than O-MDC) while at the same time was able to remove about 74% of salt (55.58% in the O-MDC). Each cycle of O-MDC and O-MDC operation lasted about 66 and 94 h, respectively, indicating a more stable current profile in the O-MDC. Moreover, sequencing test based on 16S rRNA gene showed that the anode biofilm had more diverse microbial community than anolyte sample. Proteobacteria, Firmicutes and Acidobacteria were from dominant microbial communities in anode biofilm sample. Accordingly, the results revealed that ozone can enhance MDC performance either as a desalination process or as a pre-treatment reactor for downstream desalination processes.
微生物脱盐电池（MDC）是一种新型的水脱盐方法，它基于细菌产生的电流按比例从水中去除离子物种。然而，该技术中电流产生低和去离子化不足给改进该工艺带来了挑战。在此，对使用臭氧作为新电子受体的MDC（O-MDC）与另一个独立使用氧气运行的MDC（O₂-MDC）的性能进行了评估。结果表明，在O₃-MDC和O₂-MDC中，用于20 g L NaCl脱盐时的最大开路电压分别为628和1331 mV。O₃-MDC产生的最大功率密度为4.06 W m⁻²（约比O₂-MDC高11倍），同时能够去除约74%的盐分（O₂-MDC中为55.58%）。O₃-MDC和O₂-MDC运行的每个周期分别持续约66和94小时，表明O₃-MDC中的电流分布更稳定。此外，基于16S rRNA基因的测序测试表明，阳极生物膜的微生物群落比阳极电解液样品更多样化。变形菌门、厚壁菌门和酸杆菌门是阳极生物膜样品中的优势微生物群落。因此，结果表明臭氧作为脱盐过程或作为下游脱盐过程的预处理反应器都可以提高MDC的性能。
