Quantifying the Chronic Effect of Low DO on the Nitrification Process
Our previous study indicated that a low dissolved oxygen (DO) could enrich and shift nitrifier community, making complete nitrification feasible under long-term low DO conditions. This research determined nitrifier kinetic constants, and quantified the chronic effect of low DO on the overall nitrification process. For ammonia oxidizing bacteria (AOB), the half-velocity constants of DO on the growth (KDO-g) and decay (KDO-d) were 0.29 and 0.48 mgL-1, respectively. For nitrite oxidizing bacteria (NOB), those values were 0.08 and 0.69 mgL-1, respectively. The low KDO-g values for both AOB and NOB suggest that a DO of greater than 1 mgL-1 does not provide further benefit to nitrification, and the lower KDO-g value for NOB suggests that nitrite oxidation is less impacted by a low DO. The KDO-d values of 0.48 and 0.69 mgL-1 for AOB and NOB, respectively, suggest that a low DO of less than 1 mgL-1 significantly inhibits the decay of both AOB and NOB, resulting in their enrichment. The relationship between the operational DO and required SRT for complete nitrification was developed to provide a theoretical foundation for operating an advanced wastewater treatment plant under low DO, to significantly improve aeration energy efficiency.
G. Liu and J. Wang, "Quantifying the Chronic Effect of Low DO on the Nitrification Process," Chemosphere, vol. 141, pp. 19-25, Elsevier, Dec 2015.
The definitive version is available at https://doi.org/10.1016/j.chemosphere.2015.05.088
Civil, Architectural and Environmental Engineering
Keywords and Phrases
Ammonia; Nitrite; Oxygen; Betaproteobacteria; Biochemical oxygen demand; Biomass; Chemistry; Growth; Development and aging; Nitrification; Oxidation reduction reaction; Procedures; Theoretical model; Water management; Ammonia; Betaproteobacteria; Biological Oxygen Demand Analysis; Models; Theoretical; Nitrification; Nitrites; Oxidation-Reduction; Water Purification; Half-velocity constant; Low DO aeration; Modeling; Nitrification kinetics; Nitrifier decay; Nitrifier growth
International Standard Serial Number (ISSN)
Article - Journal
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