PERFORMANCE OF IFAS USING DISPERSED MEDIA IN ORGANIC MATI ER REMOVAL AND NITRIFICATION OF WASTEWATER

IFAS Integrated Fixed Film Activated Sludge System is a hybrid wastewater treatment approach that combines attached biological growth with suspended biological growth in one tank; its main application is in upgrading existing WWTPs without the need of constructing new tanks. An experimental model was built and operated in Zenein WWTP, Giza, Egypt in order to study the performance of IFAS using dispersed media. The experimental setup was composed of three tanks: feeding tank, aeration tank, and final sedimentation tank. Media used is a rectangular PVC unit with a surface are of 223 cm^2 per piece. Experiments were conducted for 6 month to identify the optimum percentage of media occupatio:il cfthe tank volume,. and to study the effect of increasing organic matter on the treatment process. Results indicated that 40% media occupation is the best % of occupation; BOD removal efficiency reached 84.8 %, whereas it was 87.8% for COD, and 69.1% for nitrification rate 69.27%. Dispersed media proved to have better performance than fiXed media. And at increased organic loading of 500 mg COD/L, BOD removal efficiency reached 81% in average.