COD removal and phosphorus conversion in a UASB-aerobic reactor system

Abstract

This study involved the laboratory operation of a biological wastewater treatment system which combined anaerobic and aerobic processes. A synthetic industrial waste was treated for the removal of COD and the conversion of phosphorus using a UASB (Upflow Anaerobic Sludge Blanket) reactor in series with an aerobic reactor. The aspects examined ,in this study included the efficiency of the system to remove COD and convert phosphorus as well as the effects of the processes on the aerobic biomass. A synthetic waste containing 1400 mg/L of COD and 2.18 mg/L of total phosphorus was used as feed for the experiment. At an organic loading of 2.1 kg COD/m3d (based on the UASB reactor volume), the UASB-aerobic reactor system as a whole removed more than 90% of COD and 75% total phosphorus. The system is capable of exceeding these removal efficiencies but had not yet reached steady state at the end of this 136 day experiment.