Characterization of Aerobic Granular Sludge Cultivated in a Pilot Scale Bioreactor for Domestic Wastewater Treatment
Aerobic granular sludge (AGS) is an advanced technology of activated sludge process in treating domestic wastewater cultivated in sequencing batch reactor (SBR) system (AGS-SBR). In this study, biomass concentration, settling velocity (νags), granular strength and the diameter of the granules as well as morphological and structural observation of the cultivated aerobic granules, were investigated during the treatment of real domestic wastewater at temperature of 27– 30 oC. This experiment was carried out for the treatment of low-strength domestic wastewater at an organic loading rate of 0.4 – 0.7 kg COD m−3 d−1 in a SBR with a complete time cycle of 3 h. In terms of granular size, the highest average diameter of the mature granules was 3.36 mm and good biomass concentration of 14.02 g L−1 were observed in the bioreactor. The aerobic granular sludge achieved promising results in the treatment of domestic wastewater with good removal rates of 65.0 %, 49.21 % and 36.51 % for chemical oxygen demand, ammoniacal nitrogen and total phosphorus, respectively. The study demostrated that aerobic granular sludge can be the most efficient biological wastewater treatment technologies. In the meantime, this technology can reduce the footprint of the plant and eventually will come to the cost saving of the plant. Keywords - Aerobic Granular Sludge, Domestic Wastewater,Sequencing Batch Reactor, Wastewater Treatment.