表面流人工湿地提升河道水体感官品质研究

Research on Improving Sensory Quality of River Water by Surface Flow Constructed Wetland

采用黄菖蒲表面流人工湿地处理河道水体,探究表面流湿地在三个水深(25、45、65cm)条件下对河道水感官品质提升效果的影响。结果表明,黄菖蒲湿地出水浊度由35 NTU降至5NTU以下,色度由23度降至1度以下,透明度由35 cm提升至160 cm以上,且河道进水TN和TP均得到有效削减。在水深为45 cm时,湿地出水感官品质较好,营养盐去除率较高,因此选择45 cm为表面流湿地最佳水深。在此水深条件下,对湿地进出水进行粒径分析、三维荧光分析可知,河道水体中的颗粒粒径范围较广,且颗粒粒径较大,而湿地出水中颗粒物粒径基本小于1 100 nm。原水色度较高时,原水中富里酸和类蛋白的含量较高,在湿地出水中这些物质得到了较好的削减。综合粒径分析、三维荧光分析得到,20株/m2是本研究中黄菖蒲湿地的最佳种植密度。

River water was treated by a surface flow constructed wetland planted with yellow iris,and effect of water depth( 25 cm,45 cm and 65 cm) on water sensory quality improvement was explored. Effluent turbidity of yellow iris wetland decreased from 35 NTU to less than 5 NTU,chromaticity decreased from 23 degree to less than 1 degree,transparency increased from 35 cm to more than 160 cm,and the influent TN and TP were both effectively reduced. When water depth was 45 cm,the sensory quality of the wetland water was better,and the removal efficiency of nutrient was higher.Therefore,45 cm was selected as the optimal water depth of the surface wetland. Under this water depth,water quality of the influent and effluent was analyzed by particle size analysis and three-dimensional fluorescence analysis. It was found that the particle size range of the raw water was wider and the particle size was larger,but the particle size in effluent of the wetland was less than 1 100 nm. When the original chromaticity was high,fulvic acid and proteinoid in the raw water were high,and they could be effectively reduced in the wetland. Considering the results of particle size analysis and three-dimensional fluorescence analysis,20 plants/m2 was chosen to be the optimal yellow iris planting density in this study.