Ammonium Removal by Nitrification and Denitrification in an Integrated Fixed Film Activated Sludge Process

When nitrogen-containing compounds are released into the environment, they could create serious problems such as eutrophication of rivers, deterioration of water quality and potential hazard to human or animal health. Biological nitrogen removal is generally preferred over physicochemical methods due to its lower cost, lower chemical/energy requirements, and being environmental friendly. The current study aimed to evaluate the performance of a simultaneous nitrification and denitrification in a modified integrated fixed-film activated sludge (IFAS). The ammonia and chemical oxygen demand (COD) (Ammonia 25, 40, 80, 120 and 160 mg/L and COD = 500 mg/L) removal were studied by the proposed system. Two reactors in bench scale with the capacity of 13 liters were considered. Effective parameters such as hydraulic retention time, COD consumption, and the effect of loading ammonia were evaluated. Employing the BET, surface area (Sa), total pore volume (Vp), and average size of the nanostructure were 0.4026 m2/g, 3.808903 cm3/g and 44.7 nm, respectively. Results indicated that the desirable hydraulic retention time for nitrification occurred at 12. Due to higher COD consumption, there was no significant difference between the conventional IFAS and modified IFAS units. Based on the nitrification and denitrification results, the best condition for nitrifying/denitrifying performance was obtained by modified IFAS. Based on nitrification and denitrification data, the best condition for nitrifying/ denitrifying performance was obtained by modified-IFAS. Hence, the modification can be used to obtain the best activities of microbial and nitrogen removal improvement.