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Application of Design Aspects in Uniaxial Loading Machine Development
Published on: September 19, 2018
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Partial nitritation at elevated loading rates: design curves and biofilm characteristics
Alexander Schopf1, Robert Delatolla2, Kathlyn M Kirkwood3
1Department of Civil Engineering, Ottawa-Carleton Institute for Environmental Engineering, University of Ottawa, Ottawa, Canada.
Bioprocess and Biosystems Engineering
|July 28, 2019
Summary
Elevated loading rates in moving bed biofilm reactors (MBBRs) can achieve low-intensity partial nitritation. Complete nitrite production was observed at high ammonium loading rates, suppressing further oxidation.
Area of Science:
- Environmental Engineering
- Microbiology
Background:
- Wastewater treatment requires cost-effective, low-intensity systems.
- Passive operation strategies for partial nitritation are underexplored.
Purpose of the Study:
- Investigate elevated loading rates for low-intensity partial nitritation.
- Determine the impact of loading rates on nitrification kinetics and biofilm characteristics.
Main Methods:
- Utilized a moving bed biofilm reactor (MBBR) system.
- Applied elevated loading rates (3-6.5 g NH4+-N/m2 days) under controlled dissolved oxygen (5.5-7.0 mg O2/L) and temperature (19-21 °C).
- Analyzed nitrification kinetics and biofilm properties.
Main Results:
- Observed a shift in kinetics towards nitritation at elevated loading rates.
- Achieved complete partial nitritation (100% nitrite) at 6.5 g NH4+-N/m2 days.
- Thick biofilms (572 µm) and high ammonium load suppressed nitrite oxidation.
Conclusions:
- Elevated loading rates are a viable strategy for passive, low-intensity partial nitritation.
- Optimizing loading rates can control nitrification pathways in MBBRs.
- This approach offers a cost-effective solution for wastewater treatment.
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