Phosphorus fractionation in membrane-assisted biological nutrient removal processes
1Department of Civil and Environmental Engineering, University of Western Ontario, 1151 Richmond Street, London, ON, Canada, N6A 5B9.
Chemosphere
|July 7, 2009
Summary
A novel membrane bioreactor (NMBR) shows improved nitrogen and phosphorus removal from wastewater compared to the University of Cape Town adapted MBR (UMBR). This advanced wastewater treatment offers lower effluent nitrates and phosphates.
Area of Science:
- Environmental Engineering
- Microbiology
- Biotechnology
Background:
- Conventional membrane bioreactors (MBRs) face challenges in achieving high nutrient removal efficiencies.
- Optimizing MBR performance for nitrogen and phosphorus removal is crucial for sustainable wastewater management.
Purpose of the Study:
- To compare the performance of a novel membrane bioreactor (NMBR) against a conventional University of Cape Town adapted MBR (UMBR).
- To evaluate nutrient removal efficiencies, specifically total nitrogen and phosphorus, in different municipal wastewater streams.
Main Methods:
- A comparative study using two different municipal wastewaters.
- Operation of NMBR and UMBR at a fixed hydraulic retention time (6h) and sludge retention time (10d).
- Analysis of effluent nutrient concentrations and sludge phosphorus fractionation.
Main Results:
- NMBR achieved higher total nitrogen removal efficiencies (73-80%) compared to UMBR (70-77%).
- NMBR demonstrated lower effluent nitrates (1-1.7 mgL(-1) less) and phosphorus (0.5 mgL(-1) vs 0.8 mgL(-1)).
- Denitrifying phosphate accumulating organisms (DPAO) contributed significantly to phosphorus uptake in both systems, and poly-P content increased with volatile fatty acid supplementation.
Conclusions:
- The patented NMBR offers superior performance in nitrogen and phosphorus removal from municipal wastewater compared to UMBR.
- NMBR technology presents a promising advancement for enhanced wastewater treatment and nutrient recovery.
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