TABLE OF CONTENTS Pages Symposium 1 - the National Sea ...

important for the design and optimal operation of biofilters. When dealing with a shock
load, for example, nitrification rate of a biofilter can be improved through increasing
Reynolds number, by raising rotation speed of a RBC, or increasing turbulence of the
flow over a trickling filter.
Conclusions
(1) Nitrification potential was a function of substrate concentration. The relationship
between nitrification rate of a biofilm reactor and substrate concentration followed
Michaelis-Menten type equation. The maximum ammonia removal rate was above
2000 mg-N/m 2 -day.
(2) At steady-state, temperature impact to nitrification rate was not significant, especially
under high substrate concentration condition when oxygen limitations became
apparent.
(3) Oxygen limitation became more pronounced when organic substance was present.
The availability of organic matter stimulated the growth of heterotrophic bacteria,
which in turn competed with nitrifiers for limited available oxygen.
(4) Hydraulic condition was an important factor affecting oxygen and TAN mass transfer
from bulk solution to biofilms, and thus limited TAN removal rate for a nitrification
biofilm. For the same TAN concentration level, TAN removal rate at Re=66710 was
about 5 times that at Re=1668.
References
Boller, M., Gujer, W., and Tschui, M. 1994. Parameters Affecting Nitrifying Biofilm
Reactors. Water Science Technology 29(10-11):1-11.
Bovendeur, J., Zwaga, A., Lobee, B., and Blom, J. 1990. Fixed-Biofilm Reactors in
Aquacultural Water Recycle Systems: Effect of Organic Matter Elimination on
Nitrification Kinetics. Water Research 24(2):207-213.
Hagopian, D. and Riley, J. 1998. A Closer Look at the Bacteriology of Nitrification.
Aquaculture Engineering 18(4):223-250.
Horn, H. 1994. Dynamics of a Nitrifying Bacteria Population in a Biofilm Controlled by
an Oxygen Microelectrode. Water Science Technology 29(10-11):69-76.
Liu, Y. and Capdeville, B. 1994. Kinetic Behaviors of Nitrifying Biofilm Growth in
Wastewater Nitrification Process. Environmental Technology 15:1001-1013.
McHarness, D., Haug, R., and McCarty, P. 1975. Field Studies of Nitrification with
Submerged Filters. Journal of the Water Pollution Control Federation 47(2):291-309.
Moreau, M., Liu, Y., Capdeville, B., Audic, J.M., and Calvez, L. 1994. Kinetic
Behavior of Heterotrophic and Autotrophic Biofilms in Wastewater Treatment
Processes. Water Science Technologies. Vol. 29, No. 10-11. pp. 385-391.
Sharma, B. and Ahlert, R.C. 1977 Nitrification and Nitrogen Removal. Water Research
11:897-925.
Srna, R.F. and Baggaley, A. 1975. Kinetic Response of Perturbed Marine Nitrification
Systems. Journal of the Water Pollution Control Federation 47(3):472-786.
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