Formation and characterization of aerobic granules in a pilot-scale reactor for real wastewater treatment

• Published in: Huanjing kexue Vol. 35; no. 5; p. 1850
• Main Authors: Yang, Shu-Fang, Zhang, Jian-Jun, Zou, Gao-Long, Du, Zhi-Li
• Format: Journal Article
• Language: Chinese
• Published: China 01.05.2014
• Subjects: Biological Oxygen Demand Analysis; Bioreactors; Nitrogen - chemistry; Phosphorus - chemistry; Sewage - chemistry; Silicon Dioxide - chemistry; Waste Disposal, Fluid - methods; Waste Water - chemistry; X-Ray Diffraction
• ISSN: 0250-3301
• DOI: 10.13227/j.hjkx.2014.05.031

Microbial granules were successfully developed in a pilot-scale sequencing batch reactor (SBR) for the treatment of real municipal wastewater. The aerobic granules developed had good settleability with a settling velocity of > 21 mh-1. The mature granular sludge was capable of simultaneous removal of chemical oxygen demand (COD), nitrogen (N) and phosphorus (P). With the cycle of 3 h, the effluent COD, ammonium nitrogen (NH+4 -N) and total nitrogen (TN) concentrations were <50 mg L-1, <5. 0 mg L-1, and <15 mgL-1, respectively. The removal efficiency for TN and total phosphorus (TP) was about 50%. Examinations by confocallaser scanning microscopy (CLSM) showed that extracellular polymeric substances (EPS) were uniformly distributed throughout the granules, forming the granule structure matrix. X-ray diffraction (XRD) analysis indicated the presence of SiO2 and other metal oxides inside aerobic granules, implying that minerals in real wastewater might function as the seed in the initial stage of aerobic granula