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A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities
Published on: December 25, 2015
Interaction between denitrification and phosphorus removal in a sequencing batch reactor phosphorus removal system
Qiuyan Yuan1, Jan Oleszkiewicz
1Department of Civil Engineering, University of Manitoba, Canada. umyuan3@cc.umanitoba.ca
Summary
Denitrifying phosphorus accumulating organisms (DNPAOs) can remove phosphorus using nitrate as an electron acceptor. Higher nitrate levels require longer anoxic periods for effective phosphorus uptake by DNPAOs.
Area of Science:
- Environmental Microbiology
- Water Treatment Technologies
Background:
- Denitrifying phosphorus accumulating organisms (DNPAOs) are crucial for simultaneous nitrogen and phosphorus removal.
- Understanding the interplay between denitrification and phosphorus uptake is key for optimizing wastewater treatment.
Purpose of the Study:
- To investigate the simultaneous denitrification and phosphorus removal capabilities of DNPAOs.
- To determine the effect of nitrate concentration on phosphorus uptake and release dynamics.
Main Methods:
- Batch experiments were conducted to assess DNPAO performance.
- Varying nitrate concentrations were applied in the presence of a carbon source.
Main Results:
- DNPAOs effectively removed phosphorus using nitrate as an electron acceptor.
- Increased nitrate concentrations necessitated longer anoxic periods for optimal phosphorus uptake.
- Phosphorus release occurred during anaerobic phases when substrate was present, though nitrate presence hindered this process due to competition for carbon sources.
- DNPAOs demonstrated competitiveness even when nitrate was present in the anaerobic phase.
Conclusions:
- DNPAOs are capable of simultaneous denitrification and phosphorus removal.
- Nitrate concentration is a critical factor influencing the efficiency and kinetics of phosphorus removal by DNPAOs.
- DNPAOs maintain competitive phosphorus accumulating abilities under challenging conditions with co-present nitrate.
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