School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, China.
Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, People's Republic of China.
Environ Sci Pollut Res Int. 2021 Aug;28(32):43402-43416. doi: 10.1007/s11356-021-12449-0. Epub 2021 Apr 8.
Two sets of hybrid constructed wetlands (HCWs) with the first-stage aeration were used to treat actual domestic sewage in this paper, where the effects of three important factors of aeration mode, hydraulic loading rates (HLR), and aeration volume on the removal of pollutants in both HCWs were studied in contrasts. In addition, the pollutant removal efficiency, the contribution of plants, and the characteristics of biofilm in both HCWs were explored. The results of 250-day experiment showed that the TN removal capacity of HCW combining vertical flow CW with horizontal flow CW (VF-HF) was better than HCW's converse combination (HF-VF) in treatingsewage, while the removal efficiency of COD and NH-N were similar, and the concentrations of TN and COD in the effluent of VF-HF could successfully meet the National discharge requirements. Compared with the continuous aeration, the intermittent aeration only had a little effect on the removal of COD and NH-N, but could improve TN removal performance in both HCWs. Meanwhile, increasing the aeration volume was beneficial to remove NH-N but not TN in HCWs. In addition, although the pollutant removal performances in both HCWs were impacted, the removal capacity of TN in VF-HF was only affected a little, when HLR was increased by 50%. The contribution of plants' uptake accounted for about 10% to nitrogen removal and 20% to phosphorus removal in both HCWs. The biomass at the filler surface near the plant rhizosphere was greater than that in the non-rhizosphere zones, and the impact of plant rhizosphere on the nitrification activity of biofilm was significantly greater than that on denitrification activity in both HCWs.
两组采用一级曝气的复合式人工湿地（HCWs）被用于处理实际生活污水。本文对比研究了曝气方式、水力负荷率（HLR）和曝气量这三个重要因素对两组 HCWs 中污染物去除的影响。此外，还探究了污染物去除效率、植物的贡献以及两组 HCWs 中生物膜的特性。250 天的实验结果表明，在处理污水方面，垂直流 CW 与水平流 CW 相结合的 HCW（VF-HF）的 TN 去除能力优于其相反组合（HF-VF），而 COD 和 NH-N 的去除效率则相似，VF-HF 的出水 TN 和 COD 浓度可成功满足国家排放标准。与连续曝气相比，间歇曝气仅对 COD 和 NH-N 的去除略有影响，但可提高两组 HCWs 中 TN 的去除性能。同时，增加曝气量有利于去除 HCWs 中的 NH-N，但不利于去除 TN。此外，尽管两组 HCWs 的污染物去除性能受到影响，但当 HLR 增加 50%时，VF-HF 中 TN 的去除能力仅受到轻微影响。植物吸收的贡献约占两组 HCWs 中氮去除的 10%和磷去除的 20%。植物根际附近填料表面的生物量大于非根际区的生物量，并且植物根际对生物膜硝化活性的影响明显大于对反硝化活性的影响。
