Murdoch University Research Repository

Welcome to the Murdoch University Research Repository

The Murdoch University Research Repository is an open access digital collection of research
created by Murdoch University staff, researchers and postgraduate students.

Learn more

Optimisation of storage driven denitrification by using on-line specific oxygen uptake rate monitoring during SND in a SBR

Third, K., Sepramaniam, S., Tonkovic, Z., Newland, M. and Cord-Ruwisch, R. (2004) Optimisation of storage driven denitrification by using on-line specific oxygen uptake rate monitoring during SND in a SBR. Water Science and Technology, 50 (10). pp. 171-180.

Link to Published Version:
*Subscription may be required


This study builds on previous experience of maximising the formation of COD as poly-hydroxybutyrate (PHB) and now describes a feedback technique of preserving the use of PHB for denitrification resulting in enhanced nitrogen removal rather than allowing its wasteful oxidation by oxygen. The feedback technique uses on-line SOUR monitoring for detecting the end-point of nitrification and controlling the aerobic phase length accordingly. The laboratory SBR was operated such that all organic substrate (acetate) was rapidly converted to PHB, which then served as the electron donor for nitrogen removal via simultaneous nitrification and denitrification (SND) during the aerobic phase (up to 70% SND). During SBR cycling with a fixed aeration length (240 minutes), PHB was unnecessarily oxidised after ammonium depletion, resulting in little denitrification and poor total nitrogen removal (69%). However, when the aerobic phase length was controlled via the SOUR, up to 1.8 CmM PHB (58 mg L -1 COD) could be preserved, enabling improved total nitrogen removal (86%). The drop in the SOUR after ammonium depletion was a reproducible event that could be detected even when using raw wastewater and fresh activated sludge. The SOUR-control technique holds promise to build up PHB over a number of SBR cycles. While advanced oxygen-control is used for improved N-removal in several existing WWTPs, this study investigates the importance of oxygen control with relevance to PHB driven SND in sequencing batch reactors.

Item Type: Journal Article
Murdoch Affiliation(s): School of Biological and Environmental Sciences
Publisher: International Water Association Publishing
Copyright: © IWA Publishing 2004.
Publisher's Website:
Item Control Page Item Control Page