实验和经验混合长度之间的偏差的证据:在干旱的河流系统中进行多次排放现场测试
Aashish Khandelwal1, Tzion Castillo2, Ricardo González-Pinzón1
1Gerald May Department of Civil, Construction and Environmental Engineering, University of New Mexico, Albuquerque, NM USA.
Water research
|April 21, 2024
概括
目前计算河流混合区的方法已经过时,无法准确预测废水处理厂下游污染物稀释. 新的研究表明,这些经验方程不考虑变化的流量条件,可能导致广泛接触新出现的污染物,如PFAS.
科学领域:
- 环境工程 环境工程
- 河流生态 河流生态
- 水质管理水质管理
背景情况:
- 污水处理厂 (WWTP) 排放的污染物包括微塑料,药品和PFAS.
- 混合区许可证假定污染物被稀释,依赖于20世纪70年代的经验方程.
- 现有的方法在动态流量条件下和先进监测下缺乏验证.
研究的目的:
- 通过实验量化WWTP排放下游的混合长度.
- 评估传统的经验方程的准确性,以预测混合长度.
- 评估不同河流排放对污染物混合的影响.
主要方法:
- 采用拉格朗的和欧勒的监测方法来测量WWTP下游的混合.
- 在广泛的河流和WWTP排放比率 (2-22x) 中收集了数据.
- 将实验混合长度与来自既定实证方程的预测进行了比较.
主要成果:
- 经验方程无法准确地描述实验确定的混合长度.
- 实验数据显示",钟形"的混合长度随着河流排放的增加而增加.
- 经验模型不准确地预测了单调增加的混合长度.
结论:
- 混合长度的传统实证方程对于当前的环境条件是不够的.
- 流动模式 (喷射扩散,柯安达效应,流混合) 以1D模型无法捕捉的方式影响混合.
- 对混合区法规的审查是必要的,以防止对新出现的污染物的广泛暴露.
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