a. a. azimi

Background and Waste stabilization ponds as a natural treatment method have been found among successful methods in municipal wastewater treatment. They are very costeffective in energy and manpower. Low efficiency rates and vast area required are some of their drawbacks which are less attended to. Therefore this study intends to research the optimization methods in anaerobic ponds. Methods and Materials: In this experimental study, two anaerobic ponds were built in pilot scale with 48 hours detention time, 12 m2 area (6x2 m) and 4m depth. The control pond was a conventional pond; the optimized pond was built in two parts: a digestion pit and a detention time of 12 hours, and the anaerobic pond with 8 baffles with a detention time of 36 hours. The wastewater with BOD5=250 mg/l and TSS=320 mg/l from municipal network in Sabzevar, Iran was used; the pilot took one year from December 2006 to December 2007. The collected data were analyzed in Excel and Tsp7. Average removal efficiency for BOD5 and TSS in the conventional pond were 37% and 53% respectively; the figures for the optimized pond were 68% and 85% respectively. Using optimized anaerobic ponds enhances the removal efficiency rate.