Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China.
School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China.
Sci Total Environ. 2023 Dec 15;904:166811. doi: 10.1016/j.scitotenv.2023.166811. Epub 2023 Sep 4.
A novel wastewater treatment plant process was constructed to overcome the challenge of simultaneous nitrate removal and phosphorus (P) recovery. The results revealed that the P and nitrate removal efficiency rose from 39.0 % and 48.4 % to 92.8 % and 93.6 % after 136 days of operation, and the total P content in the biofilm (TP) rose from 15.8 mg/g SS to 57.8 mg/g SS. Moreover, the increase of TP changed the metabolic mode of denitrifying polyphosphate accumulating organisms (DPAOs), increasing the P concentration of the enriched stream to 172.5 mg/L. Furthermore, the acid/alkaline fermentation led to the rupture of the cell membrane, which released poly-phosphate and ortho-phosphate of cell/EPS in DPAOs and released metal‑phosphorus (CaP and MgP). In addition, high-throughput sequencing analysis demonstrated that the relative abundance of DPAOs involved in P storage increased, wherein the abundance of Acinetobacter and Saprospiraceae rose from 8.0 % and 4.1 % to 16.1 % and 14.0 %. What's more, the highest P recovery efficiency (98.3 ± 1.1 %) could be obtained at optimal conditions for struvite precipitation (pH = 7.56 and P: N: Mg = 1.87:3.66:1) through the response surface method (RSM) simulation, and the precipitates test analysis indicated that P recovery from biofilm sludge was potentially operable. This research was of great essentiality for exploring the recovery of P from biofilm sludge.
构建了一种新型废水处理厂工艺，以克服同时去除硝酸盐和磷（P）的挑战。结果表明，经过 136 天的运行，P 和硝酸盐的去除效率从 39.0%和 48.4%提高到 92.8%和 93.6%，生物膜中的总磷（TP）含量从 15.8mg/g SS 增加到 57.8mg/g SS。此外，TP 的增加改变了反硝化聚磷菌（DPAOs）的代谢模式，使富集中的磷浓度增加到 172.5mg/L。此外，酸/碱性发酵导致细胞膜破裂，从而使 DPAOs 中的聚磷酸盐和正磷酸盐以及金属磷（CaP 和 MgP）从细胞/EPS 中释放出来。此外，高通量测序分析表明，参与磷储存的 DPAOs 的相对丰度增加，其中，不动杆菌和 Sapropiraceae 的丰度从 8.0%和 4.1%增加到 16.1%和 14.0%。更重要的是，通过响应面法（RSM）模拟，可以在最佳条件下（pH=7.56，P:N:Mg=1.87:3.66:1）获得最高的磷回收率（98.3±1.1%），沉淀测试分析表明，从生物膜污泥中回收磷具有潜在的可行性。这项研究对于探索从生物膜污泥中回收磷具有重要意义。
