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Measurement of the Potential Rates of Dissimilatory Nitrate Reduction to Ammonium Based on 14NH4+/15NH4+ Analyses via Sequential Conversion to N2O
Published on: October 7, 2020
Nitrophenol removal by simultaneous nitrification denitrification (SND) using T. pantotropha in sequencing batch
1Center for Environmental Science and Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India. pradnyakulkarni@iitb.ac.in
Bioresource Technology
|December 1, 2012
Summary
This study demonstrates effective nitrophenol removal using a sequencing batch reactor (SBR) system with specialized biomass. The system achieved high removal rates for 4-nitrophenol, 2,4-dinitrophenol, and 2,4,6-trinitrophenol.
Area of Science:
- Environmental Science
- Biotechnology
- Chemical Engineering
Background:
- Nitrophenols are common industrial pollutants.
- Effective removal methods are crucial for environmental protection.
- Sequencing Batch Reactors (SBRs) offer a flexible approach to wastewater treatment.
Purpose of the Study:
- To evaluate nitrophenol removal efficiency in a lab-scale SBR.
- To assess the performance of a single sludge biomass containing Thiosphaera pantotropha.
- To investigate the impact of gradually increasing nitrophenol concentrations on removal.
Main Methods:
- Utilized four identical lab-scale sequencing batch reactors (SBRs).
- Employed a specialized single sludge biomass containing Thiosphaera pantotropha.
- Implemented a synthetic feed designed to direct Simultaneous Nitrification and Denitrification (SND) at reduced aeration (DO=2mg/L).
- Gradually increased nitrophenol concentrations from 2.5 to 200 mg/L during acclimation.
Main Results:
- Achieved 98% removal for 4-nitrophenol (4-NP).
- Observed 83-84% removal for 2,4-dinitrophenol (2,4-DNP) and 2,4,6-trinitrophenol (2,4,6-TNP).
- Demonstrated high Chemical Oxygen Demand (COD) removal rates (97-99%) for all tested nitrophenols.
- Confirmed that total nitrogen and nitrophenol removals were achieved via SND.
Conclusions:
- The SND-based SBR system with Thiosphaera pantotropha is effective for nitrophenol removal.
- The system shows promise for treating wastewater contaminated with various nitrophenols.
- Reduced aeration conditions are suitable for achieving both nitrogen and nitrophenol removal simultaneously.
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