Simultaneous nitrification–denitrification and microbial community profile in an oxygen-limiting intermittent aeration SBBR with biodegradable carriers

• Published in: Biodegradation (Dordrecht) Vol. 29; no. 5; pp. 473 - 486
• Main Authors: Feng, Lijuan, Jia, Rong, Zeng, Zhen, Yang, Guangfeng, Xu, Xiangyang
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.10.2018; Springer; Springer Nature B.V
• Subjects: Aeration; Aerobiosis; Ammonium nitrogen; Anoxia; Aquatic Pollution; Bacteria - metabolism; Batch Cell Culture Techniques; Biodegradability; Biodegradation; Biodegradation, Environmental; Biodiversity; Biofilms; Biological Oxygen Demand Analysis; Biomedical and Life Sciences; Bioreactors; Bioreactors - microbiology; Constraining; Denitrification; Environmental Pollutants - analysis; Geochemistry; Life Sciences; Microbiology; Microorganisms; Nitrification; Organic Chemicals - isolation & purification; Original Paper; Oxygen; Oxygen - metabolism; Phylogeny; Purification; Ratios; Removal; Sewage; Sewage treatment; Soil Science & Conservation; Sulfur; Sulphur; Terrestrial Pollution; Waste Management/Waste Technology; Waste Water Technology; Wastewater treatment; Water Management; Water Pollution Control; Intermittent micro-aeration cycles (IMCs); Sequencing batch biofilm reactor (SBBR); COD/N; Simultaneous nitrification and denitrification (SND); Microbial community
• ISSN: 0923-9820; 1572-9729
• DOI: 10.1007/s10532-018-9845-x

To enhance the startup and efficient simultaneous nitrification and denitrification for sewage treatment, sequencing batch biofilm reactors (SBBRs) partially coupled with rice husk were established and operated under various intermittent micro-aeration cycles (IMCs) and COD/N ratios under oxygen-limiting intermittent aeration conditions. Experimental results showed that the increase of IMCs with non-aeration/micro-aeration mode of (8 h/4 h) 1 to (2 h/1 h) 4 in a 12 h-cycle accelerated the startup performance and improved NH 4 + –N and COD removal. NH 4 + –N, TN and COD removal efficiencies were 98.7 ± 0.9, 89.2 ± 5.2 and 82.9 ± 6.7% at COD/N ratio of 7.6 with the highest IMCs in SBBR, respectively. Higher TN removal efficiencies of 87.2 ± 4.0 and 58.1 ± 3.5% were also achieved at lower COD/N ratio of 5.6 and 2.8, respectively. In SBBRs with various IMCs, facultative denitrifier like genus Acinetobacter and solid-phase denitrifier belonging to Comamonadaceae family were enriched. However, aerobic denitrifiers with function of heterotrophic nitrification like Paracoccus were favored to enrich under higher IMCs condition, and more anoxic denitrifiers like sulfur-based autotrophic denitrifier Thiothrix and heterotrophic denitrifiers like Pseudomonas and Methyloversatilis were observed at lower IMCs condition. Autotrophic nitrifier ( Nitrosomonas and Nitrosipra ) and heterotrophic nitrifiers both contributed to the efficient nitrification.