Preemptive activation of hypolimnetic oxygenation improves control of Fe and Mn in drinking water reservoirs

IF 12.4 1区环境科学与生态学 Q1 ENGINEERING, ENVIRONMENTAL

Water Research Pub Date : 2025-10-03 DOI:10.1016/j.watres.2025.124722

Cecelia E. Wood, Carly E. Bauer, Adrienne Breef-Pilz, Abigail S.L. Lewis, Nicholas W. Hammond, Ryan P. McClure, Mary F. Verne, Cayelan C. Carey, Madeline E. Schreiber

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引用次数: 0

Abstract

Seasonal anoxia in the hypolimnion of freshwater reservoirs can degrade water quality by promoting the release of iron (Fe) and manganese (Mn). To address these issues, hypolimnetic oxygenation (HOx) is an engineered treatment that aims to prevent upward diffusion of reduced Fe and Mn from anoxic sediments and to oxidize reduced Fe and Mn in the water column, enabling sedimentation and removal. However, quantification of the effect of HOx on Fe and Mn concentrations is challenging without a reference ecosystem for comparison and multiple years of monitoring data. In this study, we monitored dissolved Fe and Mn in the water column and Fe and Mn removal through sedimentation for six years in two temperate reservoirs – one with a HOx system and one without. Our results show that HOx significantly enhances Fe and Mn sedimentation in freshwater reservoirs, but sedimentation of Fe was much greater than Mn. When activated before the onset of anoxia, HOx substantially decreased the rates of Fe release into the water column. In contrast, although early HOx activation delayed Mn release, it did not decrease the Mn release rate into the water column. However, early HOx activation increased the Mn sedimentation rate. When HOx was activated after the onset of anoxia, maximum total Fe and Mn concentrations in the hypolimnion were approximately 4x and 1.6x greater than concentrations in years with preemptive activation. Our study indicates that HOx improves water quality with respect to Fe and Mn, especially when activated prior to the onset of anoxia.

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抢先激活低氧合可以改善饮用水中铁和锰的控制

季节性缺氧可通过促进铁（Fe）和锰（Mn）的释放来降低淡水水库的水质。为了解决这些问题，低氧合（HOx）是一种工程处理方法，旨在防止缺氧沉积物中还原性铁和锰的向上扩散，并氧化水柱中的还原性铁和锰，从而实现沉淀和去除。然而，在没有参考生态系统进行比较和多年监测数据的情况下，HOx对铁和锰浓度的影响的量化是具有挑战性的。在这项研究中，我们监测了水柱中溶解的铁和锰，并通过沉淀在两个温带水库中去除铁和锰，一个有HOx系统，一个没有。结果表明，HOx显著促进了淡水水库中铁和锰的沉降，但铁的沉降量远大于锰。如果在缺氧发生前激活，HOx显著降低了铁释放到水柱中的速率。相比之下，HOx的早期活化虽然延迟了Mn的释放，但并没有降低Mn向水柱的释放速率。然而，早期的HOx活化增加了Mn的沉降速率。当HOx在缺氧开始后被激活时，低铁离子中最大总Fe和Mn浓度比预先激活年份的浓度高约4倍和1.6倍。我们的研究表明，HOx可以改善水质的铁和锰，特别是在缺氧前激活。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Water Research 环境科学-工程：环境

CiteScore

20.80

自引率

9.40%

发文量

1307

审稿时长

38 days

期刊介绍： Water Research, along with its open access companion journal Water Research X, serves as a platform for publishing original research papers covering various aspects of the science and technology related to the anthropogenic water cycle, water quality, and its management worldwide. The audience targeted by the journal comprises biologists, chemical engineers, chemists, civil engineers, environmental engineers, limnologists, and microbiologists. The scope of the journal include: •Treatment processes for water and wastewaters (municipal, agricultural, industrial, and on-site treatment), including resource recovery and residuals management; •Urban hydrology including sewer systems, stormwater management, and green infrastructure; •Drinking water treatment and distribution; •Potable and non-potable water reuse; •Sanitation, public health, and risk assessment; •Anaerobic digestion, solid and hazardous waste management, including source characterization and the effects and control of leachates and gaseous emissions; •Contaminants (chemical, microbial, anthropogenic particles such as nanoparticles or microplastics) and related water quality sensing, monitoring, fate, and assessment; •Anthropogenic impacts on inland, tidal, coastal and urban waters, focusing on surface and ground waters, and point and non-point sources of pollution; •Environmental restoration, linked to surface water, groundwater and groundwater remediation; •Analysis of the interfaces between sediments and water, and between water and atmosphere, focusing specifically on anthropogenic impacts; •Mathematical modelling, systems analysis, machine learning, and beneficial use of big data related to the anthropogenic water cycle; •Socio-economic, policy, and regulations studies.