MOE Key Laboratory of Resources and Environmental Systems Optimization, North China Electric Power University, Beijing, 102206, China.
State Key Joint Laboratory of Environmental Simulation and Pollution Control, China-Canada Center for Energy, Environment and Ecology Research, UR-BNU, School of Environment, Beijing Normal University, Beijing, 100875, China; Environmental Systems Engineering Program, University of Regina, Regina, S4S 0A2, Canada.
Chemosphere. 2022 May;294:133536. doi: 10.1016/j.chemosphere.2022.133536. Epub 2022 Jan 6.
Discharge of decentralized livestock wastewater without effective treatment has become a common problem in rural areas, threatening the regional water environment. A new microcurrent-assisted multi-soil-layering (MSL) system was developed for treating rural decentralized livestock wastewater. The results showed the highest removal rates of chemical oxygen demand (COD) and total phosphorus (TP) in MSL systems reached 95.45% and 92.0%, respectively. The removal rate of total nitrogen (TN) in MSL systems ranged from 60 to 75%. The bacterial diversity changes among MSL systems showed that high-level height of bottom submergence had a positive effect on the abundance of denitrifying bacteria, while low-level height of bottom submergence had a positive impact on the abundance of nitrifying bacteria. The effect of low-level external voltage on bacterial abundance was better than that of high-level external voltage. Both high- and low-level influent C/N ratios had no significant effect on bacterial abundance. The metabolism and activity of microorganisms were promoted with microcurrent stimulation from the perspective of increased bacterial abundance in MSL systems with improved treatment performance.
未经有效处理的分散式畜禽养殖废水排放已成为农村地区的一个普遍问题，威胁着区域水环境。本研究开发了一种新型微电流辅助多土层（MSL）系统，用于处理农村分散式畜禽养殖废水。结果表明，MSL 系统对化学需氧量（COD）和总磷（TP）的去除率最高，分别达到 95.45%和 92.0%。MSL 系统对总氮（TN）的去除率在 60%至 75%之间。MSL 系统中细菌多样性的变化表明，底层淹没高度较高对反硝化菌的丰度有积极影响，而底层淹没高度较低对硝化菌的丰度有积极影响。低水平外部电压对细菌丰度的影响优于高水平外部电压。从提高处理性能的 MSL 系统中增加的细菌丰度来看，高低水平的进水 C/N 比均对细菌丰度没有显著影响。微生物的代谢和活性受到微电流刺激的促进。
