Influence of temperature on performance of an anaerobic sequencing biofilm batch reactor with circulation applied to treatment of low-strength wastewater

Abstract

The effect of temperature on the performance of an anaerobic sequencing biofilm batch reactor (ASBBR) with liquid-phase recirculation was assessed. Assays were performed using a recirculation velocity of 0.20 cm/s, 8-h cycles, and an average treated synthetic wastewater volume of 2 L/cycle with a concentration of 500 mg of Chemical Oxygen Demand (COD)/L. Operation temperatures were 15, 20, 25, 30, and 35°C. At 25, 30, and 35°C, organic matter removal efficiencies for filtered samples ranged from 81 to 83%. At lower temperatures, namely 15 and 20°C, removal efficiency decreased significantly to 61 and 65%, respectively. A first-order model could be fitted to the experimental concentration profile values. The first-order kinetic parameter value of this model varied from 0.46 to 0.81 h-1 considering the lowest and highest temperature studied. Moreover, analysis of the removal profile values allowed fitting of an Arrhenius-type equation with an activation energy of 5715 cal/mol. Copyright © 2007 by Humana Press Inc. All rights of any nature whatsoever reserved.