摘要
本研究通过批量试验评估了沸石、陶粒、石英砂、活性炭作为人工湿地基质的污染物去除效果。经过12天的处理，沸石、陶粒、石英砂、活性炭对浮游藻类的浊度、表面颜色、本色和叶绿素的去除率4～8毫米陶粒除垢率分别达到93.6%、92.1%、89.7%、91.3%，明显改善了景观水体的感官效果，TN达到地表水Ⅳ类标准，TP、高锰酸盐指数满足地表水水质为Ⅲ类。经陶粒处理后，景观水体的UV 254和UV 280值以及CDOM吸收系数均显著降低，E 250 /E 365值明显高于其他基质，表现出良好的污染物去除效果。结果表明，4 ~ 8 mm陶粒 是适合用于封闭式景观水体的CW处理工艺的基质，未来应开展长期试验以检验其污染物去除效果。
关键词： 小型景观封闭水体；基质类型；污染物去除
Abstract
In this study, pollutant removal effects of zeolite, ceramsite, quartz sand, and activated carbon were assessed its feasibility as a constructed wetland substrate using batch experiments. After 12 days of treatment, the removal rates of turbidity, surface color, true color, and chlorophyll of planktonic algae by 4~8 mm ceramic granules reached 93.6%, 92.1%, 89.7%, and 91.3%, respectively, which significantly improved the sensory effect of the landscape water. TN reached the class Ⅳ of the surface water, meanwhile, TP and permanganate index fulfilled the quality of the surface water class Ⅲ. After being treated by ceramsites, the UV254 and UV280 values, as well as CDOM absorption coefficients of the landscape water, were much lower, and the values of E250/E365 were clearly higher than other substrates, which demonstrated excellent contaminant removal effect. All results indicated that 4~8 mm ceramsites were suitable substrates when used in CWs treating closed landscape water bodies. Long-term experiments should be carried out to test its pollutants removal performance in the future.
Key words： Small landscape closed water; Substrates type; Pollutants removal
参考文献 References
[1] Nuamah A L, Li Y, Pu Y, et al. Constructed wetlands, status, progress, and challenges. The need for critical operational reassessment for a cleaner productive ecosystem [J]. Journal of Cleaner Production, 2020, 269:122340.
[2] Ji Z H, Tang W Z, Pei Y S. Constructed wetland substrates: A review on development, function mechanisms, and application in contaminants removal [J]. Chemosphere, 2021, 286:131564.
[3] Cui E P, Zhou Z C, Gao F, et al. Roles of substrates in removing antibiotics and antibiotic resistance genes in constructed wetlands: A review [J]. Science of the Total Environment, 2023, 85:160257.
[4] Chao Y, Zhang X L, Tang Y Q. Selection and optimization of the substrate in constructed wetland: A review [J]. Journal of Water Process Engineering, 2022, 49 103140.
[5] Yang Y, Zhao Y, Liu R, et al. Global development of various emerged substrates utilized in constructed wetlands [J]. Bioresource Technology, 2018, 441-452.
[6] Wang H, Xu J, Sheng L. Purification mechanism of sewage from constructed wetlands with zeolite substrates: A review [J]. Journal of Cleaner Production, 2020, 258:120760.
[7] Zhang X, Zhao S, Gao J, et al. Microbial action and mechanisms for Cr(VI) removal performance by layered double hydroxide modified zeolite and quartz sand in constructed wetlands [J]. Journal of Environmental Management, 2019, 246:636-646.
[8] Dai H L, Hu FP. Phosphorus Adsorption Capacity Evaluation for the Substrates Used in Constructed Wetland Systems: A Comparative Study [J]. Polish Journal of Environmental Studies, 2017, 26(3):1003-1010.
[9] APHA. Standard methods for the examination of water and wastewater, twentieth ed. American Public Health Association, Washington, DC, USA. 1988.
[10] Patyal V, Jaspal D, Khare K. Materials in constructed wetlands for wastewater remediation: A review [J]. Water Environment Research, 2021, 93(12):2853-2872.
[11] Xu L, Chen LQ, Zhuang M. Treating graywater using quartz sand filters: the effect of particle size, substrate combinations, and reflux ratio [J]. Desalination and Water Treatment, 2020, 131-138.