M. Mauret et al., APPLICATION OF EXPERIMENTAL RESEARCH METHODOLOGY TO THE STUDY OF NITRIFICATION IN MIXED CULTURE, Water science and technology, 34(1-2), 1996, pp. 245-252
Citations number
21
Categorie Soggetti
Water Resources","Environmental Sciences","Engineering, Civil
Nitrification is an aerobic process formed by two consecutive reaction
s: nitritation and nitratation. Using an experimental research methodo
logy, we have studied the specific effects and the possible interactio
ns between initial ammonia concentration, pH and temperature on these
two reactions as well as on the experimental conditions leading to a n
itrite build-up. In the experimental field studied (35 < [N-NH4+](o) m
g.l(-1) < 90, 15 < T degrees C < 25 and 7 < pH < 8.5), the statistic i
nterpretation of the results shows that only temperature and pH have a
significant positive effect on ammonia removal. Moreover, the effect
of these two parameters is linear. As for nitrite accumulation, the te
mperature effect is negligible and a strong interaction between [N-NH4
](o) and pH is revealed. When the values of these two variables are hi
gh, nitratation is inhibited and 50% of the nitrogen introduced at the
beginning accumulates temporarily in the Form of nitrites. The result
s clearly show that a high NH3 concentration inhibits Nitrobacter, sta
rting from between 6.6 and 8.9 mg N-NH3.l(-1). This research enables a
better understanding of the nitrite build-up phenomena which can be t
hus minimized or maximized in the case of new process of nitrogen trea
tment. Copyright (C) 1996 IAWQ.