Environmental Science and Engineering College, Dalian Maritime University, 1 Linghai Road, Dalian 116026, People's Republic of China.
Environmental Science and Engineering College, Dalian Maritime University, 1 Linghai Road, Dalian 116026, People's Republic of China.
Bioelectrochemistry. 2020 Jun;133:107481. doi: 10.1016/j.bioelechem.2020.107481. Epub 2020 Feb 11.
High-salt conditions reduce the efficiency of electricity generation and nitrogen removal in microbial fuel cells (MFCs). In this work, we propose a three-phase single-chamber MFC (TP-MFC) by setting up a phase with immobilized cells in a conventional bipolar single-chamber MFC (common MFC). Cells from Halomonas were used as the immobilized phase, because these cells secrete the compatible solute ectoine and exhibit simultaneous nitrification and denitrification (SND). This enhanced the efficiency of SND and subsequent electricity generation under high-salt conditions. The average voltage of TP-MFC generated during the stable period in the presence of 30 g/L NaCl was 439.3 mV, which was 55.2% higher than that generated in common MFC. In addition, the N-removal rate of TP-MFC at 72 h was 63.4%, which was 38.4% higher than that of common MFC. The 16S rRNA diversity analysis showed an improved abundance of Pseudomonas, Acinetobacter, Alcaligenes, and Halomonas in TP-MFC, indicating that the ectoine secreted by immobilized Halomonas conferred substantial salt-tolerance on the electrogenic bacteria growing in a high-salt environment. This paper establishes an efficient and convenient method for improving the salt tolerance of microbial flora in MFCs, which is of great significance for the application of MFCs in high-strength wastewater treatment.
高盐条件会降低微生物燃料电池（MFC）的发电效率和脱氮效率。在这项工作中，我们通过在传统的双极单室 MFC（普通 MFC）中设置固定化细胞相，提出了一种三相单室 MFC（TP-MFC）。我们选择 Halomonas 细胞作为固定化相，因为这些细胞分泌相容性溶质海藻糖，并表现出同时硝化和反硝化（SND）。这增强了在高盐条件下 SND 及其后续发电的效率。在存在 30 g/L NaCl 的稳定期内，TP-MFC 的平均电压为 439.3 mV，比普通 MFC 产生的电压高 55.2%。此外，TP-MFC 在 72 小时内的 N 去除率为 63.4%，比普通 MFC 高 38.4%。16S rRNA 多样性分析显示，在 TP-MFC 中，Pseudomonas、Acinetobacter、Alcaligenes 和 Halomonas 的丰度得到了提高，这表明固定化的 Halomonas 分泌的海藻糖赋予了在高盐环境中生长的发电细菌很强的耐盐性。本文建立了一种有效且方便的方法来提高 MFC 中微生物菌群的耐盐性，这对于 MFC 在高强度废水处理中的应用具有重要意义。
