||Waste stabilization lagoon microorganism removal efficiency and effluent disinfection with chlorine /
Johnson, Bruce A. ;
Wight, Jeffrey L. ;
Bowles, David S. ;
Reynolds, James H. ;
Middlebrooks, E. Joe
||Municipal Environmental Research Laboratory.
|| Environmental Protection Agency, Office of Research and Development [Office of Energy, Minerals, and Industry], Municipal Environmental Research Laboratory ; For sale by the National Technical Information Service,
Sewage lagoons. ;
Sewage treatment ;
Coliform bacteria ;
Mathematical models ;
Performance evaluation ;
Biochemical oxygen demand ;
||Some EPA libraries have a fiche copy filed under the call number shown.
||xxiii, 360 pages : illustrations, graphs ; 28 cm.
This project had two major objectives: (1) to evaluate the amenability of algae-laden lagoon effluent to chlorine disinfection; and (2) to evaluate the performance of a multi-cell lagoon system in removing coliform bacteria by natural means without the need for disinfection. Results indicate that adequate disinfection was obtained with combined chlorine residual within a contact period of 60 minutes. Filtered effluent was found to exert less chlorine demand tha unfiltered. Temperature, sulfide, and total chemical oxygen demand were the most important factors affecting the chlorine dose necessary to achieve a specified bacteriological quality. A mathematical model was developed and a series of design curves were constructed for use in selecting the optimal chlorine dosages needed for achieving prescribed levels of disinfection. Total and fecal coliform removal in the lagoon system was related to hydraulic residence time. Coliform die-away rate was 16 times greater in summer months than in winter months.
Contract no. 68-03-2151. July 1979. Includes bibliographical references (pages 216-226). Microfiche.