Title

Quantifying the Chronic Effect of Low DO on the Nitrification Process

Abstract

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.

Department(s)

Civil, Architectural and Environmental Engineering

Comments

This research was partially supported by a grant from the Army Research Lab (ARL) through the Leonard Wood Institute (LWI) and Frontier Environmental Technology, LLC.

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)

1879-1298

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2015 Elsevier, All rights reserved.

PubMed ID

26086562

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