Continuous Pre‐Anoxic and Aerobic Digestion of Waste Activated Sludge
Publication: Journal of Environmental Engineering
Volume 116, Issue 5
Abstract
Conventional aerobic sludge stabilization requires extensive energy input. Incorporation of endogenous nitrate respiration (ENR) into the aerobic‐digestion system offers the energy‐saving advantage. In the ENR system, nitrate instead of oxygen is utilized for the biomass destruction. In this study, continuous preanoxic and aerobic digestion of waste‐activated sludge is studied to evaluate its effectiveness for volatile suspended solids (VSS) destruction and nitrogen removal. The ENR occurs in the anoxic digester because of the recycling of nitrate from the aerobic digester. The anoxic effluent, in turn, provides a high pH and adequate buffer capacity for enhancing the subsequent aerobic decay and nitrification. Two experimental runs, differing in hydraulic‐detention time in anoxic and aerobic tanks, are conducted with the same recycle rate. The results indicate that total nitrogen removal is approximately 25%, with 40% VSS destruction. The denitrification/nitrification efficiencies and rates are also determined. A mathematical model developed from the mass balance of biomass, ammonium, and nitrate reasonably predicts transient responses of these parameters.
Get full access to this article
View all available purchase options and get full access to this article.
References
1.
Anderson, B. C., and Mavinic, D. S. (1984). “Aerobic sludge digestion with pH control‐preliminary investigation.” J. Water Pollut. Control Fed., 56(7), 889–897.
2.
Argaman, Y. (1981). “Design and performance charts for single sludge nitrogen removal systems.” Water Res., 15(7), 841–847.
3.
Barnard, J. L. (1975). “Biological nutrient removal without the addition of chemicals.” Water Res., 9(5), 485–490.
4.
Bishop, P. L., and Farmer, M. (1978). “Fate of nutrient during aerobic digestion.” J. Envir. Engrg. Div., ASCE, 104(5), 967–980.
5.
Carnahan, B., Luther, H. A., and Wilkes, J. O. (1969). Applied numerical methods. John Wiley and Sons, New York, N.Y.
6.
Christensen, M. H., and Harremoes, P. (1978). “Nitrification and denitrification in wastewater treatment.” Water Pollution Microbiology, R. Mitchell, ed., 2, John Wiley and Sons, New York, N.Y.
7.
Ganczarczyk, J., Hamoda, M. F., and Wong, M. (1980). “Aerobic digestion of sludge solids.” Water Res., 14(6), 627–634.
8.
Hashimito, S., Fujita, M., and Terai, K. (1982). “Stabilization of waste activated sludge through anoxic‐aerobic digestion process.” Biotech. and Bioeng., 24(8), 1789–1802.
9.
Kim, M. H. (1989). “Anoxic sludge digestion of waste activated sludge.” Thesis presented to the University of Maryland, at College Park, Md., in partial fulfillment of the requirements for the degree of Master of Science.
10.
Kim, M. H., and Hao, O. J. (1990). “Comparison of activated sludge stabilizationunder aerobic or anoxic condition.” J. Water Pollut. Control Fed., 62(2), 160–168.
11.
Krishnamoorthy, R., and Loehr, R. C. (1989). “Aerobic sludge stabilization—Factors affecting kinetics.” J. Envir. Engrg., ASCE, 115(2), 283–301.
12.
Matsuda, A., et al. (1988). “Behavior of nitrogen and phosphorus during batch aerobic digestion of waste activated sludge—Continuous aeration and intermittent aeration by control of DO.” Water Res., 22(12), 1495–1502.
13.
Mavinic, D. S., and Koers, D. A. (1982). “Fate of nitrogen in aerobic sludge digestion.” J. Water Pollut. Control Fed., 54(4), 352–360.
14.
McClintock, S. A., et al. (1988). “Nitrate versus oxygen respiration in the activated sludge process.” J. Water Pollut. Control Fed., 60(3), 342–350.
15.
Painter, H. A. (1970). “A review of the literature on inorganic nitrogen metabolism in microorganisms.” Water Res., 4(5), 393–450.
16.
“Phosphate removal.” (1987). EPA‐625/1‐87/001, U.S. EPA, Ctr. Envir. Res. Info., Cincinnati, Ohio.
17.
Shieh, W. K., Chen, C. Y., and Chang, S. D. (1982). “Preliminary study of a suspended growth predenitrification system.” Biotech. and Bioengrg., 24(11), 2557–2572.
18.
Standard methods for the examination of water and wastewater. (1985). 16th Ed., Amer. Public Health Assoc., Washington, D.C.
19.
Warner, A. P. C., Ekama, G. A., and Maris, G. V. R. (1986). “The activated sludge process—IV. Application of the general kinetic model to anoxic‐aerobic digestion of waste activated sludge.” Water Res., 20(8), 943–958.
Information & Authors
Information
Published In
Journal of Environmental Engineering
Volume 116 • Issue 5 • September 1990
Pages: 863 - 879
Copyright
Copyright © 1990 ASCE.
History
Published online: Sep 1, 1990
Published in print: Sep 1990
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.