Water-Circulating Aerator: Optimizing Structure and Predicting Water Flow Rate and Oxygen Transfer
Publication: Journal of Hydraulic Engineering
Volume 137, Issue 6
Abstract
Thermal stratification is a common phenomenon in deep lakes and reservoirs, which often results in water-quality deterioration, including such problems as hypolimnetic anoxia, the release of pollutants from sediments, and algal blooms. Hypolimnetic oxygenation and destratification are the two commonly used methods for resolving these water-quality problems. A new water-quality improvement device, the water-circulating aerator, was designed to destratify lakes and reservoirs, by circulation and oxygenation of upper and lower layers of water. The design of the structure of the water-circulating aerator is detailed. Three mathematical models were built to optimize this structure, estimate the rate of water flow in the aerator, and calculate the rate of oxygen transfer from air bubbles to water in the aerator. These models were verified by experiments. The water-circulating aerator system has been successfully applied in a stratified reservoir to increase dissolved oxygen to reduce the releasing of ammonia-nitrogen from sediments under anoxic conditions.
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Acknowledgments
The experiments were carried out in the Key Laboratory of Northwest Water Resource, Environment and Ecology, Ministry of Education (MOE), China. The study is jointly supported by the National Ministry of Science and Technology under the National High-tech Programming of China (863 Project, UNSPECIFIED2007AA06Z302), as well as by the National Natural Science Foundation of China (NSFC, UNSPECIFIED50778147). The writers would like to express their gratitude to the agencies involved and participants of the study.
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Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 137 • Issue 6 • June 2011
Pages: 659 - 667
Copyright
© 2011 American Society of Civil Engineers.
History
Received: Jun 26, 2007
Accepted: Oct 21, 2010
Published online: Oct 26, 2010
Published in print: Jun 1, 2011
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