Nitrite Accumulation at Low Copper Concentration in a Submerged Partial Bionitrification Reactor
Objectives : Effects of various Cu2+ concentrations in the synthetic wastewater on nitrite accumulation was investigated in a submerged partial biofilter reactor (SPBNR). Methods : Experiments were carried out at the constant operational conditions (T=35℃; pH=9.0 and DO=2.0 mg O2/L) by varying th...
Main Authors: | , |
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Format: | Article |
Language: | English |
Published: |
Korean Society of Environmental Engineers
2021-06-01
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Series: | 대한환경공학회지 |
Subjects: | |
Online Access: | https://www.jksee.or.kr/journal/view.php?number=4342 |
Summary: | Objectives : Effects of various Cu2+ concentrations in the synthetic wastewater on nitrite accumulation was
investigated in a submerged partial biofilter reactor (SPBNR).
Methods : Experiments were carried out at the constant operational conditions (T=35℃; pH=9.0 and DO=2.0 mg
O2/L) by varying the concentrations between 5-50 mg Cu2+/L. The SPBNR, which was operated in an upward flow
mode, set-up consisted of a cylindrical stainless steel. The support materials filling ratio was about 23% of the
total reactor volume. The SPBNR was inoculated with microorganism drawn from a batch experimental biological
reactor operated about one month by using the synthetic wastewater composition.
Results and Discussion : Before exposure to Cu2+, the highest loading rate of 1.3 g NH4-N/(m2.day) was
determined under the operational conditions. Addition of 5 μg Cu2+/L into the waters promoted the activity of
organisms and the loading rate achieved to 1.6 g NH4-N/(m2.day). At the control operational condition, the ratio of
NO2-N/NOx-N was determined as 0.74, while the ratio increased to 0.78 at the Cu2+ concentration of 5 μg/L.
Conclusions : Results indicated that the ammonium oxidizing bacteria (AOB) is more stimulated than the nitrite
oxidizing bacteria (NOB) at the concentration of 5 μg Cu2+/L. However, approximately equal NH4-N removal rate
(ANRR) and NO2-N accumulation rate (NiAR) losses indicated that the AOB and NOB are approximately equally
effected at the inlet concentrations of 35 and 50 μg Cu2+/L. |
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ISSN: | 1225-5025 2383-7810 |