Mathematical Model for the Biofilm–Activated Sludge Reactor
Publication: Journal of Environmental Engineering
Volume 131, Issue 4
Abstract
A steady state mathematical model is developed for describing the completely mixed biofilm–activated sludge reactor (hybrid reactor). The model is derived by simultaneously considering Monod kinetics expressions and Fickian’s diffusion theory for substrate in biofilm. In addition, it includes the basic concepts, which describe both culture (suspended and attached) and the competition between them for limiting substrate. By using this model the suspended biomass concentration can be obtained for this system. Subsequently, the other remaining parameters of the system can be computed. Therefore it helps to design and operate the hybrid reactor under different conditions for any given set of kinetic parameters. The utility of the model has been explained for a given set of data and verified by comparing with another solution. It is found that for the same set of data, the model is accurate in the results. The model has been presented in more than one form, each form having an explicit solution of the system. Compared with other solutions of such a system, the model provides a good tool for describing such a system based on fundamental principles.
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Acknowledgments
The writers would like to thank Professor Bruce E. Rittmann, Northwestern University, Evanston, for providing his valuable literature. The writers also appreciate the help provided by Professor Rashmi Gaur, IIT Roorkee, India, in modifying the language of this paper.
References
Andreottola, G., Foladori, P., Magazzi, M., and Tatano, F. (2000). “Experimental comparison between MBBR and activated sludge for the treatment of municipal wastewater.” Water Sci. Technol., 41(4–5), 375–382.
Chen, G. H., Huang, J. C., and Irene, M. C. L. (1997). “Removal of rate-limiting organic substances in a hybrid biological reactor.” Water Sci. Technol., 35(6), 81–89.
Chen, S. K., and Cheng, S. S. (1994). “The enhancement of nitrification by indirect aeration and kinetic control in a submerged reactor.” Water Sci. Technol., 30(11), 79–89.
Gebara, F. (1999). “Activated sludge biofilm wastewater treatment system.” Water Res., 33(1), 230–238.
Hamoda, M. F., and Al-Sharekh, H. A. (2000). “Performance of a combined biofilm–Suspended growth system for waste water treatment.” Water Sci. Technol., 41(1), 167–175.
Heath, M. S., Wirtel, S. A., and Rittmann, B. E. (1990). “Simple design of the biofilm processes using normalized loading curves.” Res. J. Water Pollut. Control Fed., 62(2), 185–192.
Kim, B. R. (1992). “Approximate solution for fluidized-bed biofilm model.” Water Res., 26(9), 1271–1275.
Kim, B. R., and Suidan, M. T. (1989). “Approximate algebraic solution for a biofilm model with the Monod kinetic expression.” Water Res., 23(12), 1491–1498.
Lawrence, A. W., and McCarty, P. L. (1970). “Unified basis for biological treatment design and operation.” J. Sanit. Eng. Div., Am. Soc. Civ. Eng., 96(3), 757–778.
Lee, C. Y. (1992). “Model for biological reactors having suspended and attached growths.” Environ. Eng., 118(6), 982–987.
Lessel, T. H. (1994). “Upgrading and nitrification by submerged biofilm reactors experiences from a large scale plant.” Water Sci. Technol., 29(10-11), 167–174.
Martinez, S. G., and Luciano, J. D. (1992). “Aerobic submerged biofilm reactors for wastewater treatment.” Water Res., 26(6), 825–833.
Rittmann, B. E. (1982a). “Comparative performance of the biofilm reactor types.” Biotechnol. Bioeng., 24, 1341–1370.
Rittmann, B. E. (1982b). “The effect of shear stress on biofilm loss rate.” Biotechnol. Bioeng., 24, 501–506.
Rittmann, B. E., and McCarty, P. L. (2001). Environmental biotechnology: Principles and applications, McGraw-Hill, New York.
Sáez, P. B., and Rittmann, B. E. (1988). “Improved pseudo-analytical solution for steady-state biofilm.” Biotechnol. Bioeng., 32(3), 379–385.
Sáez, P. B., and Rittmann, B. E. (1992). “Accurate pseudo-analytical solution for steady-state biofilms.” Biotechnol. Bioeng., 39(7), 790–793.
Suidan, M. T., and Wang, Y. T. (1985). “Unified analysis of biofilm kinetics.” Environ. Eng., 111(5), 634–646.
Suidan, M. T., Wang, Y. T., and Kim, B. R. (1989). “Performance evaluation of biofilm reactors using graphical techniques.” Water Res., 23(7), 837–844.
Tsuno, H., Somiya, I., Matsumoto, N., and Sasai, S. (1992). “Attached growth reactor for BOD removal and nitrification with polyurethane foam medium.” Water Sci. Technol., 26(9–11), 2035–2038.
Williamson, K., and McCarty, P. L. (1976). “A model for substrate utilization by bacterial biofilm.” J. Water Pollut. Control Fed., 48(1), 9–24.
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© 2005 ASCE.
History
Received: May 9, 2003
Accepted: May 17, 2004
Published online: Apr 1, 2005
Published in print: Apr 2005
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