Dynamic Model for UASB Reactor Including Reactor Hydraulics, Reaction, and Diffusion
Publication: Journal of Environmental Engineering
Volume 123, Issue 3
Abstract
A dynamic model has been developed to describe upflow anaerobic sludge blanket (UASB) reactors from several aspects including reactor hydraulics, biological reaction kinetics, and mass transfer within anaerobic granules. A flow model of a nonideal continuously stirred tank reactor (CSTR) followed by a dispersion plug flow reactor (PFR) was used to simulate the reactor hydraulics as observed from a LiCl tracer study. The dynamic model based on this flow model was then evaluated by a set of acetate impulse data and verified with a data set from a two-step acetate feed increase experiment from a bench-scale UASB reactor. The model describes UASB reactor performance well. Simulation results indicate significant effects of reactor nonideal flow, diffusional resistance, as well as degradation kinetics on overall substrate utilization rate. Sensitivity analyses on model parameters Ks, km, KL, D, R, and nonideal flow factors revealed granule size has a strong impact on the reactor performance. The effect of KL is not significant. Reactor mixing was improved by an increase in biogas production.
Get full access to this article
View all available purchase options and get full access to this article.
References
1.
Alphenaar, P. A., Perez, M. C., and Lettinga, G.(1993). “The influence of substrate transport limitation on porosity and methanogenic activity of anaerobic sludge granules.”Appl. Microbiol. Biotechnol., 39, 276–280.
2.
Ames, W. F. (1977). Numerical methods for partial differential equations. W. Rheinboldt, ed., Academic Press, Inc., San Diego, Calif.
3.
Andrews, J. F.(1969). “A mathematical model for the continuous culture of microorganisms utilizing inhibitory substrate.”Biotechnol. Bioengrg., 10, 707–723.
4.
Andrews, G.(1988). “Fluidized-bed bioreactors.”Biotechnol. and Genetic Engrg. Rev., 6, 151–178.
5.
Andrews, J. F., and Graef, S. P. (1971). “Dynamic modeling and simulation of the anaerobic digestion process.”Anaerobic biological treatment process, Vol. 105, Am. Chemical Soc., Washington, D.C., 126–162.
6.
Atkinson, B., and Davies, I. J.(1974). “The overall rate of substrate uptake (reaction) by microbial films. Part I. A biological rate equation.”Trans. Inst. Chemical Engrs., 52, 248–259.
7.
Atkinson, B., and Daoud, I. (1970). “Diffusion effects within microbial films.”Trans. Inst. Chemical Engrs., 48, T245–T254.
8.
Atkinson, B., and How, S. Y. (1974). “The overall rate of substrate uptake (reaction) by microbial films.”Trans. Inst. Chemical Engrs., 52, 260– 268.
9.
Benefield, L., and Molz, F.(1984). “A model for the activated sludge process which considers wastewater characteristics, floc behavior and microbial population.”Biotechnol. Bioengrg., 26, 352–361.
10.
Bennett, C. O., and Myers, J. E. (1982). Momentum, heat and mass transfer, 3rd Ed., McGraw-Hill Book Co., Inc., New York, N.Y.
11.
Bolle, W. L., van Breugel, J., van Eybergen, G. C., Kossen, N. W. F., and van Gils, W.(1985). “An integral dynamic model for the UASB reactor.”Biotechnol. Bioengrg., 28, 1621–1636.
12.
Bolte, J. P., and Hill, D. T.(1993). “A comprehensive dynamic model of attached growth anaerobic fermenters.”Trans. ASAE, 36(6), 1805–1814.
13.
Buffière, P., and Steyer, J. P.(1995). “Comprehensive modeling of methanogenic biofilms in fluidized bed systems: mass transfer limitations and multisubstrate aspects.”Biotechnol. Bioengrg., 48, 725–736.
14.
Carr, A. D., and O'Donnell, R. C.(1977). “The dynamic behavior of an anaerobic digestor.”Progress in Water Technol., 9, 727–738.
15.
De Beer, D., Huisman, J. W., Van den Heuvel, J. C., and Ottengraf, S. P. P.(1992). “The effect of pH profiles in methanogenic aggregates on the kinetics of acetate conversion.”Water Res., 26(10), 1329–1336.
16.
Harremoës, P.(1976). “The significance of pore diffusion to filter denitrification.”J. Water Pollution Control Fedn., 48(2), 377–388.
17.
Hill, D. T., and Barth, C. L.(1977). “A dynamic model for simulation of animal waste digestion.”J. Water Pollution Control Fedn., 10, 2129–2143.
18.
Inoue, Y., and Koyama, K.(1988). “Mechanism of volatile fatty acid removal in a fixed biofilm methane fermentation reactor.”Water Sci. Technol., 20(11), 377–383.
19.
Kissel, J. C., McCarty, P. L., and Street, R. L.(1984). “Numerical simulation of mixed culture biofilm.”J. Envir. Engrg., ASCE, 110(2), 393–411.
20.
LaMotta, E. J.(1976). “Internal diffusion and reaction in biological films.”Envir. Sci. Technol., 10(8), 765–774.
21.
Lens, P. N. L., De Beer, D., Cronenberg, C. C. H., Houwen, F. P., Ottengraf, S. P. P., and Verstraete, W. H.(1993). “Heterogeneous distribution of microbial activity in methanogenic aggregates: pH and glucose microprofiles.”Appl. Envir. Microbiol., 59(11), 3803–3815.
22.
Lin, S. H.(1991). “A mathematical model for a biological fluidized bed reactor.”Chemical Tech. Biotechnol., 51, 473–482.
23.
Mosey, F. E.(1983). “Mathematical modeling of the anaerobic digestion process: regulatory mechanisms for the formation of short-chain volatile acids from glucose.”Water Sci. Technol., 15(8), 209–219.
24.
Nilsson, B. K., and Karlsson, H. T.(1989). “Diffusion rates in a dense matrix of methane-producing microorganisms.”J. Chemical and Tech. Biotechnol., 44, 255–260.
25.
Rittmann, B. E.(1982). “The effect of shear stress on biofilm loss rate.”Biotechnol. Bioengrg., 24, 501–506.
26.
Rittmann, B. E., and McCarty, P. L.(1980). “Model of steady-state-biofilm kinetics.”Biotechnol. Bioengrg., 22, 2343–2357.
27.
Rozzi, A. S., Merlinio, S., and Passino, R.(1985). “Development of a four population model of the anaerobic degradation of carbohydrates.”Envir. Technol. Letters, 6, 610–619.
28.
Shieh, W., Mulcahy, L. T., and LaMotta, E. J. (1982). “Mathematical model for the fluidized bed biofilm reactor.”Enzyme Microbiol. Technol., 4(Jul.), 269–276.
29.
Speece, R. E.(1988). “A survey of municipal anaerobic sludge digestors and diagnostic activity assays.”Water Res., 22, 365–372.
30.
Wu, M. M. (1995). Characterization of performance and monitoring of the Upflow Anaerobic Sludge Blanket Reactor,” PhD thesis, Michigan State Univ., East Lansing, Mich.
31.
Wu, M. M., Criddle, C. S., and Hickey, R. F.(1995). “Mass transfer and temperature effects on substrate utilization in brewery granules.”Biotechnol. Bioengrg., 45, 465–475.
Information & Authors
Information
Published In
Journal of Environmental Engineering
Volume 123 • Issue 3 • March 1997
Pages: 244 - 252
Copyright
Copyright © 1997 American Society of Civil Engineers.
History
Published online: Mar 1, 1997
Published in print: Mar 1997
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.