人工湿地反应性填料开发及其脱氮除磷性能研究

Development of reactive fillers in constructed wetland and its performance of nitrogen and phosphorus removal

摘要:

【目的】人工湿地填料作为反硝化电子供体可以高效且稳定地脱氮除磷，但是填料的选用方式和作用机理尚不明确。【方法】本文以磁黄铁矿、菱铁矿和农业废弃物(木屑等)为人工湿地填料，研究了其对人工湿地反硝化脱氮除磷的效果。【结果】结果显示，质量比1:1的矿石组合和木屑以3:1的质量比作为混合填料，驯化8个周期后NO₃^--N和PO₄^3--P的平均去除率达到88.6%和88.9%。扫描电子显微镜(scanning electron microscopy, SEM)、X射线光电子能谱(X-ray photoelectron spectroscopy, XPS)、X射线衍射仪(X-ray diffraction, XRD)和群落分析结果表明，微生物能有效利用矿石及其次生产物和木屑进行高效和持久的脱氮除磷，脱氮除磷功能菌硫杆菌(Thiobacillus)、罗姆布茨菌(Romboutsia)和溶杆菌(Lysobacter)得到了富集。【结论】本研究为人工湿地实际应用中新型填料的选择提供理论依据与指导意义。

Abstract:

[Objective] Constructed wetland fillers as denitrification electron donors can remove nitrogen and phosphorus efficiently and stably, but the selection method and mechanism of filler are still unclear. [Methods] In this study, pyrrhotite, siderite and agricultural waste (sawdust, etc.) were used as fillers in constructed wetlands, and their effects on denitrification, nitrogen and phosphorus removal in constructed wetlands were studied. [Results] The results show that the ore combination with a mass ratio of 1:1 and wood chips are used as a mixed filler with a mass ratio of 3:1, the removal rates of NO₃^--N and PO₄^3--P reached 88.6% and 88.9% after eight cycles of domestication. The results of scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and community analysis showed that the microorganisms could effectively use the ore and its secondary products and sawdust for efficient and lasting nitrogen and phosphorus removal, and the functional bacteria Thiobacillus, Romboutsia and Lysobacter were enriched. [Conclusion] This study provides theoretical basis and guiding significance for the selection of new fillers in the practical application of constructed wetlands.