Continuous-Flow Aerobic Granular Sludge Treatment of Dairy Wastewater

Abstract

The authors conducted a study on treating synthetic dairy wastewater using aerobic granular sludge (AGS) in a laboratory-scale continuous flow reactor (CFR) system. The system consisted of an anaerobic reactor, an aerobic reactor, and a settling sedimentation tank, with different hydraulic retention times tested over a 90-day period. The study monitored sludge characteristics and effluent treatment performance and found that the system achieved excellent removal rates for chemical oxygen demand and total carbon, exceeding 90%. As a result, the effluent met Portuguese laws for direct release into the water environment. Moreover, the study found that the AGS system improved the sludge sedimentation capacity from 272 to 80 mL/g, demonstrating its effectiveness as a viable treatment alternative for this type of effluent.