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Millifluidics for Chemical Synthesis and Time-resolved Mechanistic Studies
Published on: November 28, 2013
Kinetics of 4-nitrophenol biodegradation in a sequencing batch reactor
M Concetta Tomei1, M Cristina Annesini, Roberta Luberti
1Istituto di Ricerca sulle Acque, Consiglio Nazionale delle Ricerche, Via Reno 1, 00198, Roma, Italy. tomei@irsa.rm.cnr.it
Water Research
|August 12, 2003
Summary
This study investigated 4-nitrophenol (4NP) biodegradation in sequencing batch reactors. Results show periodic systems enhance bacterial capabilities for xenobiotic compound degradation, with removal rates increasing with the 4NP/COD ratio.
Area of Science:
- Environmental Microbiology
- Biochemical Engineering
- Wastewater Treatment
Background:
- 4-nitrophenol (4NP) is a common pollutant requiring effective degradation methods.
- Sequencing batch reactors (SBRs) offer a promising platform for treating recalcitrant organic compounds.
- Understanding biodegradation kinetics is crucial for optimizing treatment processes.
Purpose of the Study:
- To investigate the biodegradation kinetics of 4-nitrophenol (4NP) in a sequencing batch reactor (SBR).
- To evaluate the impact of a biogenic substrate fraction on 4NP removal efficiency.
- To model the relationship between 4NP removal rate and its concentration in the feed.
Main Methods:
- Kinetic tests were performed on biomass acclimated to mixed substrates (4NP and biogenic) and 4NP alone.
- The Haldane equation was used to describe substrate inhibition kinetics.
- The fraction of biomass involved in 4NP biodegradation was estimated as a function of 4NP concentration.
Main Results:
- 4NP removal kinetics followed a substrate inhibition pattern described by the Haldane equation.
- No significant benefit was observed from the presence of a biogenic substrate fraction on 4NP removal.
- A positive correlation was found between the 4NP maximum removal rate and the 4NP/COD(TOT) ratio in the feed.
Conclusions:
- Periodic systems, like SBRs, are effective in enhancing bacterial potential for xenobiotic compound biodegradation.
- High removal rates, short acclimation periods, and good sludge settling characteristics were observed.
- The study provides insights into optimizing SBR performance for 4NP removal.
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