Evaluation of an aerobic granular sludge reactor with biological filtration (AGS-BF reactor) in municipal wastewater treatment: A new configuration

Abstract

Aerobic Granular Sludge (AGS) technology is considered promising, but many aspects are being studied and developed to increase system reliability. In this regard, the research assessed the performance of a conventional AGS (R1) sequencing batch reactor (SBR) system compared to a new AGS design through the inclusion of a biological filter (BF) compartment in the upper zone (R2), treating municipal wastewater. BF insertion in R2 improved total nitrogen removal (> 85 %) and effluent clarification. Effluent total suspended solids (TSS) average values of 44.1 and 17.1 mg/L were found for R1 and R2, respectively. Sludge production was evaluated, and the yield coefficient (Y) and sludge concentration were different in the two reactors. The new system (R2) can be an interesting alternative to improve some aspects of conventional AGS reactors, such as denitrification and nitrite accumulation, effluent TSS concentration, and system reliability increase during periods of instability and granules breakage.