Praphon Kemmadamrong creator Chongrak Polprasert Chairperson Tran, Francis T. Co-Chairperson Verink, J. Examination Committee Mora, Jean-Claude Examination Committee Tyagi, R. D. Examination Committee Royal Norwegian Government Scholarship Donor text series technical report th Bangkok Asian Institute of Technology 1992 continuing eng 189 leaves Experiments on ABR were conducted to investigate its efficiency on organic carbon removal. Laboratory scale ABR units, made of PVC with dimensions of 0.25 x 0.15 x 0.32 m3 (width x depth x length), were used to treat the dissolved air flotation pre-treated slaughterhouse wastewater whose COD concentrations were 480 - 730 mg/L. The steady state performance was evaluated under organic loading rates (OLR) from 0.67 to 4.73 g COD/(L.d) and hydraulic retention time (HRT) of 2.5 to 26 h. The ABR was started up at an OLR of 0.67 g COD/(L.d) and at HRT of 26 h at ambient temperature (30 to 35' C during day time and 25 to 30' C during night time). The ABR unit was found to perform satisfactorily when operating from low OLR of 0.67 g COD/(L.d) up to 4.73 g COD/(L.d) at HRT of 2.5 h, in which the treatment efficiency of 75% was reached on a total COD basis and of 84% on a filtered COD basis. Based on COD mass balance in the ABR unit, sludge accumulation factor (Xacc) was in the range of 0.16 to 0.39 g VSS/g CODrcmovcd{u2022} and the conversion of COD removed into methane was in the range of 0.44 to 0.78 g CH4-COD/g CODrcmovcd· The sludge activities varied in the range of 0.066 to 0.293 kg CH4-COD/(kg VSS.d). Biagas produced contained 20 to 27% nitrogen, 69 to 73% methane and 2 to 4% carbon dioxide. Pilot-scale ABR experiments were conducted by using two or three upflow reactors in series. The results showed that between the OLR of 0.10 - 0.86 g COD/(L.d), the significant decrease of COD concentration within the first reactor was observed. The COD removal rates were found to increase from 0.09 to 0.66 g COD/(L.d) with increasing OLR from 0.10 to 0.86 g COD/(L.d); resulting in an average treatment efficiency of 77 -.86%. The results obtained from batch tests were used in computer simulation to determine the constant and reaction orders. The constant C of Compartments 1, 2, 3 and 4 were found to be 3.8x10- 7 , 1.9x10- 5 , 0.586 and 0.522, respectively and the reaction orders of Compartments 1, 2, 3 and 4 were 3.9, 3.1, 1 and 1, respectively. The finite difference method of the model coupling mass transfer into a biofloc with the reaction was applied to simulate the ABR performance. The model simulation of the laboratory-scale ABR process showed that the observed and predicted effluent dissolved COD concentrations agreed well between the OLR of 1.82 - 2.14 g COD/(L.d). (ii) The overall results obtained from this study have shown that ABR process is efficient for the treatment of slaughterhouse wastewater and compares favorably with other anaerobic systems. A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Engineering, School of Environment, Resources and Development Thesis (Ph.D.) - Asian Institute of Technology, 1992 Sewage Purification Biological treatment Asian Institute of Technology. http://203.159.5.9/ait-thesis/detail.php?q=B16477 http://203.159.5.9/ait-thesis/detail.php?q=B16477 191197 20260817162223.0