Model-Based Evaluation of Denitrifying P Removal in a Two-Sludge System
Publication: Journal of Environmental Engineering
Volume 127, Issue 2
Abstract
The anaerobic-anoxic-nitrification (A2N) process has been proved as a two-sludge system for denitrifying dephosphatation, based on denitrifying phosphorus-removing bacteria. Optimization of biological processes traditionally occurs by pilot-scale experiments. However, mathematical modeling may minimize pilot-scale experiments although it cannot completely predict or replace a reality. For this reason, an activated sludge model in AQUASIM 2.0 simulated the A2N process. The used model originated from the Delft model for bio-P removal and activated sludge model No. 2 for COD and N removal. The model was first verified on its description of a laboratory A2N system. The following simulations confirmed the experimental conclusion that an influent biodegradable COD:N = 3.4 mg COD/mg N (biodegradable COD:P = 26.7 mg COD/mg P) was an optimal ratio to realize full nitrification and complete denitrifying dephosphatation. Simulations also demonstrated the behavior of the A2N process under the different COD/N, COD/P, solids retention time (days), temperature, and split ratios. Simulations indicated that the COD/ was an actual governing factor in denitrifying dephosphatation and that in practice a short aerobic period following the anoxic phase was needed to obtain a stable system.
Get full access to this article
View all available purchase options and get full access to this article.
References
1.
Bortone, G., Libelli, S. M., Tilche, A., and Wanner, J. ( 1999). “Anoxic phosphate uptake in the DEPHANOX process.” Water Sci. and Technol., 40(4–5), 177–185.
2.
Bortone, G., Malaspina, F., Stante, L., and Tilche, A. ( 1994). “Biological nitrogen and phosphorus removal in an anaerobic/anoxic sequencing batch reactor with separated biofilm nitrification.” Water Sci. and Technol., 30, 303–313.
3.
Bortone, G., Saltarelli, R., Alonso, V., Sorm, R., Wanner, J., and Tilche, A. ( 1996). “Biological anoxic phosphorus removal—The DEPHANOX process.” Water Sci. and Technol., 34(1–2), 119–128.
4.
Brdanovic, D. ( 1998). “Modeling biological phosphorus removal in activated sludge systems.” PhD thesis, IHE and TU Delft, Balkema, Rotterdam, The Netherlands.
5.
Brdanovic, D., van Loosdrecht, M. C. M., Versteeg, P., Hooijmans, C. M., Alaerts, G. J., and Heijnen, J. J. ( 2000). “Modeling COD, N, and P removal in a full-scale WWTP Harden Waarderpolder.” Water Res., 34(3), 846–858.
6.
Eikelboom, D. H. ( 1991). “The role of competition between floc-forming and filamentous bacteria in bulking of activated sludge.” Proc., 143–1149.
7.
Ekama, G. A., and Wentzel, M. C. ( 1999). “Difficulties and developments in biological nutrient removal technology and modeling.” Water Sci. and Technol., 39(6), 1–11.
8.
Gujer, W., Henze, M., Mino, T., Matsuo, T., Wentzel, M. C., and Marais, G. v. R. ( 1995). “The activated sludge model No. 2: Biological phosphorus removal.” Water Sci. and Technol., 31(2), 1–11.
9.
Hao, X., Doddema, H. J., and van Groenestijn, J. W. ( 1996). “Use of contact tank to enhance denitrification in oxidation ditches.” Water Sci. and Technol., 34(1–2), 195–202.
10.
Henze, M., et al. ( 1999). “Activated sludge model No. 2d.” Water Sci. and Technol., 39(1), 165–182.
11.
Jenicek, P., Bortone, G., Cech, J. S., Wanner, J., and Tilche, A. ( 1993). “New configuration of NDEBPR system—Experimental verification with municipal wastewater.” Newsletter of the IAWQ Specialist Group on Activated Sludge Population Dynamics, 5(2), 11–15.
12.
Kuba, T., van Loosdrecht, M. C. M., and Heijnen, J. J. ( 1996a). “Phosphorus and nitrogen removal with minimal COD requirement by integration of nitrifying dephosphatation and nitrification in a two-sludge system.” Water Res., 30(7), 1702–1710.
13.
Kuba, T., Wachtmeister, A., van Loosdrecht, M. C. M., and Heijnen, J. J. ( 1996b). “A metabolic model for biological phosphorus removal by denitrifying organisms.” Biotech. Bioengrg., 52, 685–695.
14.
Kuba, T., Wachtmeister, A., van Loosdrecht, M. C. M., and Heijnen, J. J. ( 1994). “Effect of nitrate on phosphorus release in biological phosphorus removal systems.” Water Sci. and Technol., 30, 263–269.
15.
McClintock, S. A., Randall, C. W., and Pattarkine, V. M. ( 1993). “Effects of temperature and mean cell residence time on biological nutrient removal processes.” Water Envir. Res., 65(5), 110–118.
16.
Murnleitner, E., Kuba, T., van Loosdrecht, M. C. M., and Heijnen, J. J. ( 1997). “An integrated metabolic model of the aerobic and denitrifying biological phosphorus removal process.” Biotech. Bioengrg., 54, 434–450.
17.
Reichert, P. ( 1994). Concepts underlying a computer program for the identification and simulation of aquatic systems, EAWAG, Dübendorf, Switzerland.
18.
Smolders, G. J. F. ( 1995). “A metabolic model of the biological phosphorus removal.” PhD thesis, TU Delft, The Netherlands.
19.
Smolders, G. J. F., van der Mei, J., van Loosdrecht, M. C. M., and Heijnen, J. J. ( 1994). “Stoichiometric model of the aerobic metabolism of the biological phosphorus process.” Biotechnol. Bioengrg., 44, 837–848.
20.
Sorm, R., Wanner, J., Saltarelli, R., Bortone, G., and Tilche, A. ( 1997). “Verification of anoxic phosphate uptake as the main biochemical mechanism of the `DEPHANOX' process.” Water Sci. and Technol., 35(10), 87–94.
21.
van Loosdrecht, M. C. M. ( 1996). “A comparison between models for biological phosphorus removal.” Med. Fac. Landbouww, University of Gent, 61/4a, 1753–1760.
22.
van Veldhuizen, H. M., van Loosdrecht, M. C. M., and Heijnen, J. J. ( 1999). “Modeling biological phosphate and nitrogen removal in a full scale activated sludge process.” Water Res., 33(16), 3459–3468.
23.
Wanner, J., Cech, J. S., and Kos, M. ( 1992). “New process design for biological nutrient removal.” Water Sci. and Technol., 25(4–5), 445–448.
Information & Authors
Information
Published In
Journal of Environmental Engineering
Volume 127 • Issue 2 • February 2001
Pages: 112 - 118
History
Received: Mar 15, 2000
Published online: Feb 1, 2001
Published in print: Feb 2001
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.