Enhanced biological phosphorus removal in a sequencing batch reactor using propionate as the sole carbon source
Article first published online: 28 OCT 2003
Copyright © 2003 Wiley Periodicals, Inc.
Biotechnology and Bioengineering
Volume 85, Issue 1, pages 56–67, 5 January 2004
How to Cite
Pijuan, M., Saunders, A.M., Guisasola, A., Baeza, J.A., Casas, C. and Blackall, L.L. (2004), Enhanced biological phosphorus removal in a sequencing batch reactor using propionate as the sole carbon source. Biotechnol. Bioeng., 85: 56–67. doi: 10.1002/bit.10813
- Issue published online: 29 DEC 2003
- Article first published online: 28 OCT 2003
- Manuscript Accepted: 15 JUL 2003
- Manuscript Received: 24 APR 2003
- Generalitat de Catalunya; Ministerio de Ciencia y Tecnología; Comisión interministerial de ciencia y tecnología (CICYT). Grant Number: FI0036; REN2000-0670/TECNO
- polyphosphate accumulating organisms (PAO);
- enhanced biological phosphorus removal (EBPR);
- volatile fatty acids (VFA);
- fluorescence in situ hybridization (FISH);
An enhanced biological phosphorus removal (EBPR) system was developed in a sequencing batch reactor (SBR) using propionate as the sole carbon source. The microbial community was followed using fluorescence in situ hybridization (FISH) techniques and Candidatus ‘Accumulibacter phosphatis’ were quantified from the start up of the reactor until steady state. A series of SBR cycle studies was performed when 55% of the SBR biomass was Accumulibacter, a confirmed polyphosphate accumulating organism (PAO) and when Candidatus ‘Competibacter phosphatis’, a confirmed glycogen-accumulating organism (GAO), was essentially undetectable. These experiments evaluated two different carbon sources (propionate and acetate), and in every case, two different P-release rates were detected. The highest rate took place while there was volatile fatty acid (VFA) in the mixed liquor, and after the VFA was depleted a second P-release rate was observed. This second rate was very similar to the one detected in experiments performed without added VFA.
A kinetic and stoichiometric model developed as a modification of Activated Sludge Model 2 (ASM2) including glycogen economy, was fitted to the experimental profiles. The validation and calibration of this model was carried out with the cycle study experiments performed using both VFAs. The effect of pH from 6.5 to 8.0 on anaerobic P-release and VFA-uptake and aerobic P-uptake was also studied using propionate. The optimal overall working pH was around 7.5. This is the first study of the microbial community involved in EBPR developed with propionate as a sole carbon source along with detailed process performance investigations of the propionate-utilizing PAOs. © 2003 Wiley Periodicals, Inc.