Performance of an anaerobic baffled reactor (ABR) treating high strength baker's yeast manufacturing wastewater

Baker's yeast production industry is one of the most polluting industries, which generates large volumes of high strength, bad smell, and dark brown color wastewater. In this study, the interactive effects of hydraulic retention time (HRT) and up-flow velocity (V-up) on the performance of an anaerobic baffled reactor (ABR) in treating baker's yeast wastewater were investigated. The region of exploration for the process was taken as the area enclosed by HRT (2-6 days), and V-up (2-4 m/h) boundaries. In order to carry out a comprehensive analysis of the performance of this reactor and to study the biogas production process, the indicative parameters viz., COD removal, color removal, effluent total volatile fatty acids (TVFAs), pH, Delta TA (effluent total alkalinity - influent total alkalinity), effluent bicarbonate alkalinity (BA), methane yield, CH4 fraction in the biogas and specific methanogenic activity (SMA), were studied as the response. The maximum color and chemical oxygen demand (COD) removal efficiencies with influent COD of 15,000 mg/l were 43.01% and 95.13%, respectively. The maximum methane yield, CH4 fraction in the biogas, and SMA were modeled to be 0.451 CH4/g CODremd, 75.3% and 0.32 g COD-CH4/g VSS d, respectively under HRT of 2 days and V-up m/h. (C) 2014 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.