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表面流动建造湿地的水力效率和混合动力:设计,植被现象学和气候变化的影响
Charlotte Dykes1, Jonathan Pearson1, Gary D Bending2
1School of Engineering, University of Warwick, CV4 7AL, Coventry, UK.
Water research
|July 2, 2025
概括
由于设计和运营因素,表面流构造湿地 (CWs) 的水力效率较差. 然而,营养物质的去除更受植被和季节性条件的影响,这表明需要改进CW管理.
科学领域:
- 环境工程 环境工程
- 废水处理技术 废水处理技术
- 基于自然的解决方案
背景情况:
- 表面流动建造湿地 (CWs) 是废水处理的关键基于自然的解决方案,在处理厂和接收环境之间起缓冲作用.
- 虽然CWs是有效的,但由于设计局限性和对污染物运输缺乏了解,它们的液压性能往往不够优,这会影响处理效率.
- 诸如植被,基板和流水动力学等因素显著影响CWs中的停留时间和污染物-净化相互作用.
研究的目的:
- 调查跨季节气候变化,植被周期和运行条件对全尺度表面流量CW的液压性能和污染物去除效率的影响.
- 确定影响液压低效率的关键因素,如植被CW电池中的短路和死区.
- 在不同的环境条件下提供现场规模的数据,以优化CW设计和管理策略.
主要方法:
- 在2022-2023年期间使用罗达胺WT染料和度传感器进行了五次追踪测试活动,以评估四个相互连接的CW电池中的季节性液压行为.
- 使用包括平均停留时间,液压效率,有效体积比,短路和分散系数在内的指数来描述液压性能.
- 收集了高分辨率LiDAR植被扫描,营养度和气候监测的同时数据,以与液压性能相关联.
主要成果:
- 平均居住时间因季节而异,从秋季的30.03小时到夏季的47.67小时.
- 80%的标记器测试表明液压效率差 (λ <0.5),55%显示细胞体积超过50%的死区,由细胞几何学,进出口设计,高负载率和密集的植被驱动.
- 尽管液压效率低下,但营养物质的去除主要取决于植被生长阶段和季节性水的物理化学条件,而不是液压性能.
结论:
- 表面流量CW经常表现出由设计,操作和植被密度影响的显著液压低效率.
- 在CW中,营养物质的去除对生物和季节性因素比对液压性能偏差更敏感.
- 改进的设计和管理策略对于优化CW液压和处理性能至关重要,特别是考虑到气候变化.
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