Toggle Main Menu Toggle Search

Open Access padlockePrints

Low-dissolved-oxygen nitrification in tropical sewage: An investigation on potential, performance and functional microbial community

Lookup NU author(s): Vincent How, Professor Thomas CurtisORCiD

Downloads


Licence

This is the authors' accepted manuscript of an article that has been published in its final definitive form by IWA Publishing, 2018.

For re-use rights please refer to the publisher's terms and conditions.


Abstract

© IWA Publishing 2018. Intensive aeration for nitrification is a major energy consumer in sewage treatment plants (STPs). Low-dissolved-oxygen (low-DO) nitrification has the potential to lower the aeration demand. However, the applicability of low-DO nitrification in the tropical climate is not well-understood. In this study, the potential of low-DO nitrification in tropical setting was first examined using batch kinetic experiments. Subsequently, the performance of low-DO nitrification was investigated in a laboratoryscale sequential batch reactor (SBR) for 42 days using real tropical sewage. The batch kinetic experiments showed that the seed sludge has a relatively high oxygen affinity. Thus, the rate of nitrification was not significantly reduced at low DO concentrations (0.5 mg/L). During the operation of the low-DO nitrification SBR, 90% of NH4-N was removed. The active low-DO nitrification was mainly attributed to the limited biodegradable organics in the sewage. Fluorescence in-situ hybridisation and 16S rRNA amplicon sequencing revealed the nitrifiers were related to Nitrospira genus and Nitrosomonadaceae family. Phylogenetic analysis suggests 47% of the operational taxonomic units in Nitrospira genus are closely related to a comammox bacteria. This study has demonstrated active low-DO nitrification in tropical setting, which is a more sustainable process that could significantly reduce the energy footprint of STPs.


Publication metadata

Author(s): How SW, Lim SY, Lim PB, Aris AM, Ngoh GC, Curtis TP, Chua ASM

Publication type: Article

Publication status: Published

Journal: Water Science and Technology

Year: 2018

Volume: 77

Issue: 9

Pages: 2274-2283

Print publication date: 01/05/2018

Online publication date: 28/03/2018

Acceptance date: 15/03/2018

Date deposited: 05/06/2018

ISSN (print): 0273-1223

ISSN (electronic): 1996-9732

Publisher: IWA Publishing

URL: https://doi.org/10.2166/wst.2018.143

DOI: 10.2166/wst.2018.143


Altmetrics

Altmetrics provided by Altmetric


Share