Comparison of nitrogen removal rates and nitrous oxide production from enriched anaerobic ammonium oxidizing bacteria in suspended and attached growth reactors

• Published in: Journal of environmental science and health. Part A, Toxic/hazardous substances & environmental engineering Toxic/hazardous substances & environmental engineering, 2014-06, Vol.49 (7), p.851-856
• Main Authors: Panwivia, Supaporn, Sirvithayapakorn, Sanya, Wantawin, Chalermraj, Noophan, Pongsak (Lek), Munakata-Marr, Junko
• Format: Article
• Language: English
• Subjects: Ammonium Compounds - metabolism; anammox; Applied sciences; attached growth; Bacteria; Bacteria, Anaerobic - metabolism; Biological and medical sciences; Biological treatment of waters; Bioreactors - microbiology; Biotechnology; Comparative analysis; Culture; Enrichment; Environment and pollution; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; Gas Chromatography-Mass Spectrometry; General purification processes; Hydrogen-Ion Concentration; Industrial applications and implications. Economical aspects; Nitrogen; Nitrogen - metabolism; Nitrogen removal; Nitrogen removal efficiency; nitrous oxide; Nitrous Oxide - metabolism; Nitrous oxides; Oxidation; Oxidation-Reduction; Pollution; Polystyrene; Polystyrenes; Reactors; suspended growth; Waste Water - chemistry; Wastewaters; Water Pollutants, Chemical - metabolism; Water Purification - methods; Water treatment and pollution
• ISSN: 1093-4529; 1532-4117
• DOI: 10.1080/10934529.2014.882674

Attached growth-systems for the anaerobic ammonium oxidation (anammox) process have been postulated for implementation in the field. However, information about the anammox process in attached growth-systems is limited. This study compared nitrogen removal rates and nitrous oxide (N 2 O) production of enriched anammox cultures in both suspended and attached growth sequencing batch reactors (SBRs). Suspended growth reactors (SBR-S) and attached growth reactors using polystyrene sponge as a medium (SBR-A) were used in these experiments. After inoculation with an enriched anammox culture, significant nitrogen removals of ammonium (NH 4 + ) and nitrite (NO 2 − ) were observed under NH 4 + :NO 2 − ratios ranging from 1:1 to 1:2 in both types of SBRs. The specific rates of total nitrogen removal in SBR-S and SBR-A were 0.52 mg N/mg VSS-d and 0.44 mg N/mg VSS-d, respectively, at an NH 4 + :NO 2 − ratio of 1:2. N 2 O production by the enriched anammox culture in both SBR-S and SBR-A was significantly higher at NH 4 + :NO 2 − ratio of 1:2 than at NH 4 + :NO 2 − ratios of 1:1 and 1:1.32. In addition, N 2 O production was higher at a pH of 6.8 than at pH 7.3, 7.8, and 8.3 in both SBR-S and SBR-A. The results of this investigation demonstrate that the anammox process may avoid N 2 O emission by maintaining an NH 4 + :NO 2 − ratio of less than 1:2 and pH higher than 6.8.