Brown and Caldwell Home Page
Technical Papers RECENT PAPERS    ALL PAPERS      LOG IN

Brown and Caldwell engineers and scientists are technical and thought leaders in the environmental sector. Meet the people who have been advancing innovation for more than 70 years.
Author      Title/Abstract      

Performance of Alternative Algae Removal Systems
Author: Denny S. Parker
Date: 5/205
Presented at the Special Seminar on Ponds as a Wastewater Treatment Alternative University of Texas, Austin, Texas July 1976

A vexing problem facing use of oxidation ponds is suspended solids (SS) (principally algae) in the pond effluent. A national survey by Barsom has shown that the facultative type of oxidation pond has a median effluent suspended solids level of 70 mg/l and a median BOD5 concentration of 42 mg/l (1). No generally applicable effluent requirements for industry are available; however, EPA has often rendered the level of performance that will be expected of oxidation ponds in industrial applications as equivalent to secondary treatment. The EPA definition of secondary treatment for publically owned treatment works is a mean monthly value of 30 mg/l or less for SS and BOD5. The bulk of the BOD5 in oxidation pond effluents is associated with suspended matter in these effluents; therefore, compliance with permit requirements for both BOD5 and SS can normally be obtained through reductions in the level of suspended solids in the pond effluent. The focus of this paper is to examine the performance obtainable from the alternative algae removal techniques in terms of suspended solids removal. Mistakes made in the past can teach as much as the successes and therefore both techniques which have failed to measure up and those that have proven viable are considered.