ABSTRACT
Aerobic granulation technology has been applied for the high-efficiency treatment of a wide variety of wastewater including toxic wastewater, and it has been demonstrated in pilot-scale plants. The pilot-scale aerobic granular sludge sequencing batch reactor (SBR) was initiated by seeding mature aerobic granules harvested from a laboratory-scale SBR. The physical strength of aerobic granules, expressed as integrity coefficient, was 96.0% in the pilot-scale SBR and 96.9% in the laboratory-scale SBR, that is, aerobic granules developed in the laboratory-scale SBR were comparable with those in the pilot-scale SBR. Seed granules had a light grey color with a black core, which is suspected to be due to the sulfide generated by sulfate-reducing bacteria during storage, while fresh aerobic granules often have brownish-yellow color. Successful startup of the pilot-scale aerobic granular sludge SBR by seeding stored granules was demonstrated to be feasible. Aerobic granulation directly from activated sludge flocs with municipal wastewater was successfully demonstrated in a pilot-scale plant in the Netherlands.
