The use of pure oxygen to remove nitrogen gas and oxygenate fish culture rearing water
Westers, H. (1989). The use of pure oxygen to remove nitrogen gas and oxygenate fish culture rearing water, in: De Pauw, N. et al. (Ed.) Aquaculture: a biotechnology in progress: volume 1. pp. 1053-1057 In: De Pauw, N. et al. (1989). Aquaculture: a biotechnology in progress: volume 1. European Aquaculture Society: Bredene. ISBN 90-71625-03-6. 1-592 pp., more |
Available in | Author | | Document type: Conference paper
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Abstract | From 1978 through 1983 the State of Michigan designed and constructed three new salmonid production hatcheries. All three facilities are on specific pathogen-free spring and well water sources. Water quality meets or exceeds the US Environmental Protection Agency (1978/80) standards for fish culture except for dissolved oxygen and nitrogen gas. Packed columns were incorporated to satisfy these two parameters. Even then, fish performance was not satisfactory. After in-depth investigations, it was concluded that low level (101-103%) nitrogen gas supersaturation can be a serious stressor with the potential to inflict high mortalities on rainbow, brown, and lake trout fingerlings. Injecting pure oxygen was the method chosen to eliminate nitrogen gas saturation. The oxygen is generated on-site with Xorbox PSA oxygen generators (90-95% purity). The oxygen is introduced into sealed columns. Flooding in the column creates a partial vacuum. The nitrogen gas is thus displaced with oxygen. Under the proper operating conditions, dissolved oxygen levels are 100% or more, dissolved nitrogen as well as total dissolved gas (TDG) levels less than 100%. Oxygen absorption efficiency is around 50%. These changes in the dissolved gas levels have resulted in dramatically improved fish rearing success. |
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