School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, Anhui, 230009, China; Key Laboratory of Nanominerals and Pollution Control of Anhui Higher Education Institutes, Hefei University of Technology, Hefei, Anhui, 230009, China.
School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, Anhui, 230009, China; Key Laboratory of Nanominerals and Pollution Control of Anhui Higher Education Institutes, Hefei University of Technology, Hefei, Anhui, 230009, China.
Environ Pollut. 2022 Dec 1;314:120213. doi: 10.1016/j.envpol.2022.120213. Epub 2022 Sep 20.
In recent years, Feammox has made it possible to remove NH-N under anaerobic conditions; however, its application in practical wastewater treatment processes has not been extensively reported. In this study, an up-flow anaerobic biological filter based on limonite (Lim-UAF) was developed to facilitate long-term and stable treatment of domestic sewage. Lim-UAF achieved the highest removal efficiency of chemical oxygen demand (COD) and NH-N at a hydraulic retention time (HRT) of 24 h (Stage II). Specifically, the COD and NH-N content decreased from 240.8 and 30.0 mg/L to about 7.5 and 0.35 mg/L, respectively. To analyze the potential nitrogen removal mechanism, the Lim-UAF was divided into three layers according to the height of the reactor. The results showed that COD and NH-N removal had remarkable characteristics in Lim-UAF. More than 55.0% of influent COD was removed in the lower layer (0-30 cm) of Lim-UAF, while 60.2% of NH-N was removed in the middle layer (30-60 cm). Microbial community analysis showed that the community structure in the middle and upper layers (60-90 cm) was relatively similar, but quite different from that of the lower layer. Heterotrophic bacteria were dominant in the lower layer, whereas iron-reducing and iron-oxidizing bacteria were enriched in the upper and middle layers. The formation of secondary minerals (siderite and Fe(OH)) indicated that the Fe(III)/Fe(II) redox cycle occurred in Lim-UAF, which was triggered by the Feammox and NDFO processes. In summary, limonite was used to develop a single-stage wastewater treatment process for simultaneously removing organic matter and NH-N, which has excellent application prospects in domestic sewage treatment.
近年来，Feammox 技术使得在厌氧条件下去除 NH-N 成为可能；然而，其在实际废水处理过程中的应用尚未得到广泛报道。本研究开发了一种基于针铁矿的上流式厌氧生物滤池（Lim-UAF），以实现对生活污水的长期稳定处理。Lim-UAF 在水力停留时间（HRT）为 24 h（第二阶段）时达到了最高的 COD 和 NH-N 去除效率。具体而言，COD 和 NH-N 的含量分别从 240.8 和 30.0 mg/L 降低至约 7.5 和 0.35 mg/L。为了分析潜在的脱氮机制，根据反应器的高度将 Lim-UAF 分为三层。结果表明，COD 和 NH-N 的去除在 Lim-UAF 中具有显著的特征。超过 55.0%的进水 COD 在 Lim-UAF 的下层（0-30 cm）中被去除，而 60.2%的 NH-N 在中层（30-60 cm）中被去除。微生物群落分析表明，中上层（60-90 cm）的群落结构相对相似，但与下层的群落结构有很大的不同。异养菌在下层占主导地位，而铁还原菌和铁氧化菌在上层和中层得到富集。次生矿物（菱铁矿和 Fe(OH)）的形成表明，Fe(III)/Fe(II) 氧化还原循环在 Lim-UAF 中发生，这是由 Feammox 和 NDFO 过程触发的。综上所述，利用针铁矿开发了一种同时去除有机物和 NH-N 的单级废水处理工艺，在生活污水处理方面具有广阔的应用前景。
