Aerobic Granular Sludge with Granular Activated Carbon for Enhanced Biological Phosphate Removal from Domestic Wastewater

Aerobic granular sludge (AGS) is an emerging replacement for activated sludge for advanced and sustainable wastewater treatment. This study examined the beneficial effect of granular activated carbon (GAC) addition on AGS formation and sewage treatment in tropical climates. GAC shortened the start-up period for granulation by minimizing sludge washout. Ammonium was removed effectively through partial nitrification and denitritation. Enhanced biological phosphate removal was established with ~98% removal efficiencies. Improved granulation, enrichment of polyphosphate-accumulating organisms, and establishment of enhanced biological phosphate removal pathways in tropical climates recommend GAC addition as a simple and potential start-up strategy for AGS-based biological wastewater treatment.