Baskaran, Kanagaratnam creator Chongrak Polprasert Chairperson I, Fude Examination Committee Vigneswaran, Saravanamuthu Examination Committee The Roya l Netherland Government Scholarship Donor text th Bangkok Asian Institute of Technology 1988 monographic eng 100 p. Laboratory experiments were carried out on Attached Growth Activated Sludge Process (AGASP) with volume of attached-growth media in the aeration tank varied at 5%, 10%, and 15% of the aeration tank volume. Different organic loadings (F /M ratio) and different solid retention time(9 ) of the reactors were operated to investigate the c process kinetics and process efficiency. The experiments were carried out in three phases. In the first phase, the 9 were varied from 5 days c to 20 days at a constant organic loading of 0. 3 kg COD/ (kg MLSS. d). In the second phase the optimum 9 was fixed while the organic loadings c were varied from 0. 3 to 1. 0 kg COD/ (kg MLSS. d). Synthetic waste (sodium acetate and ammonium sulfate as main ingredients for carbon and nitrogen sources) was utilized as feed. The hydraulic retention time(9) and influent NH3 -N concentration were maintained at 8 hours and 65 mg/L, respectively, throughout the first two phases of experiments. In the third phase the 9 and the Organic Loading were fixed c at 10 days and 0.3 kg COD/(kg MLSS.d), respectively while the in fluent NH3 -N concentration was increased to 100 mg/L . Experimental results from the first phase revealed that the 9 c of 10 days in all AGASP reactors provided the optimum process efficiency with respect to Carbonaceous and nitrogenous compound removal. At this 9c the carbon (COD) removal was 97% and NH3 -N concentration in the effluent was not detectable. In the second phase, complete NH3 -N removal was observed in the AGASP reactors with 5% and 10% media at organic loadings between 0.3 - 1.0 kg COD/(kg MLSS . d). The COD removal in all four reactors we re between 94% - 98%. In third phase, when the AGASP reactors were fed with a high strength nitrogenous waste (NH3 -N = 100 mg/L). The AGASP reactor with 15% media gave t he optimum NH3 -N removal efficiency of 95%. The experimental results obtained suggested that the installation of 10% media in the aeration tank of an activated sludge reactor will provide a high degree of COD and NH3 -N removal. AGASP with 10% media was found to produce an effluent which should effluent standards when operated at organic 1 . 0 kg COD/(kg MLSS.d) . satisfy most stringent loadings be tween 0.3 - A mathematical model established based on a comination of MONOD expression and diffusion equation could predict the effluent quality of t h e AGASP . A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Environment, Resources and Development Thesis (M.Eng.) - Asian Institute of Technology, 1988 Sewage Purification Activated sludge process Asian Institute of Technology. http://203.159.5.9/ait-thesis/detail.php?q=B18880 http://203.159.5.9/ait-thesis/detail.php?q=B18880 120399 20260817172215.0