October 12, 2017

Superoxygenation for Water Quality Management Webinar

(Hosted by Wastewater Technology Committee)

Presentation (PDF)
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Richard Speece, Centennial Professor Emeritus of Environmental Engineering, Vanderbilt University
David Clidence, President, ECO2 Technologies

Oxygen costs approximately 1/10 as much as peroxide and nitrate. Superoxygenation technology is able to efficiently dissolve pure oxygen into water, raising the dissolved oxygen (DO) concentration to 100 mg/L or more and able to retain it in solution without effervescent loss. Many water quality problems are related to low or zero DO. Superoxygenation technology thus enables many water quality problems to be solved by raising the DO high enough and maintaining it long enough in the aqueous phase. Odor problems can be solved by either:
1. Allowing the odors to form and then capturing and treating the off gas
2. Preventing the odor formation in the first place. 
Superoxygenation technology to elevated DO levels enables the second alternative. 

1. Odors from force mains and primary clarifiers can be eliminated if the DO were raised to a sufficiently high level e.g. 20 to over 100 mg/L and kept in solution, so that anaerobic conditions can never form with their obnoxious side effects of sulfide generation. This avoids the need to cover primary clarifiers and treat the off gas.

2. Iron and manganese and hydrogen sulfide could be eliminated in the stratified hypolimnion of reservoirs if adequate DO could be maintained throughout the stratification period until the Fall turnover.

3. Rising sludge in secondary clarifiers can be eliminated if the DO of the mixed liquor entering the secondary clarifier could be raised sufficiently high e.g. 20 mg/L, so that the anaerobic conditions which result in denitrification in the sludge blanket can never form.

4. If the DO in treated municipal effluents from wastewater treatment plants were raised to a concentration equal to the ultimate BOD, e.g. 30 to 60 mg/L DO, there would be no net consumption of DO resources from the receiving waters and thus discharge into water quality limited receiving waters could be allowed.

5. DO supplementation of canals and slow-moving rivers can be achieved by withdrawing a sidestream, passing it through the Superoxygenation device and returning it to the water body with provision for immediate dilution back down to background DO.

6. Water quality degradation in drinking water distribution systems could be avoided if the DO of the treated water entering the distribution system was sufficiently high so that anaerobic conditions would not develop in the far reaches of the distribution system where there is little flow. Case histories and operating data from the many operating installations will be given to demonstrate the efficacy of this Superoxygenation technology.