State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China.
State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China; College of Environment and Ecology, Chongqing University, Chongqing, 400044, China.
Environ Pollut. 2021 Apr 1;274:116604. doi: 10.1016/j.envpol.2021.116604. Epub 2021 Jan 27.
The effects of voltage intensity on the nutrient removal performance and microbial community in the iron electrolysis-integrated aerobic granular sludge (AGS) system were investigated over a period of 15 weeks. Results revealed that the application outcomes of iron electrolysis for AGS systems relied on voltage intensity. When a constant voltage of 1.5 V was applied, the sludge granulation was most obviously accelerated with a specific growth rate of the sludge diameter of 0.078 day, and the removal efficiencies of total nitrogen (TN) and total phosphorus (TP) increased by 14.1% and 20.2%, respectively, compared to the control reactor (without the iron electrolysis-integration). Moreover, the AGS developed at different voltages included different microbial communities, whose shifts were driven by the Fe content and the average diameter of AGS. Both heterotrophic nitrifiers and mixotrophic denitrifiers were significantly enriched in the AGS developed at 1.5 V, which effectively enhanced TN removal. Together with the response of the functional genes involved in Fe, N, and P metabolism, the electrolytic iron-driven nutrient degradation pathway was further elaborated. Overall, this study clarified the optimum voltage condition when iron electrolysis was integrated into the AGS system, and revealed the enhancement mechanism of this coupling technology on nutrient removal during the treatment of low-strength municipal wastewater.
在 15 周的时间内，研究了电压强度对铁电解集成好氧颗粒污泥（AGS）系统中养分去除性能和微生物群落的影响。结果表明，铁电解对 AGS 系统的应用效果取决于电压强度。当施加 1.5V 的恒定电压时，污泥颗粒化最明显加速，污泥直径的比生长速率为 0.078 天，总氮（TN）和总磷（TP）的去除效率分别比对照反应器（无铁电解集成）提高了 14.1%和 20.2%。此外，在不同电压下开发的 AGS 包含不同的微生物群落，其变化是由 Fe 含量和 AGS 的平均直径驱动的。在 1.5V 下开发的 AGS 中，异养硝化菌和混合营养反硝化菌得到了显著富集，这有效地增强了 TN 的去除。与参与 Fe、N 和 P 代谢的功能基因的响应一起，进一步阐述了电解铁驱动的养分降解途径。总的来说，本研究阐明了将铁电解集成到 AGS 系统中的最佳电压条件，并揭示了该耦合技术在处理低强度城市污水时对养分去除的增强机制。
