Exploring nutrient removal mechanisms in column-type SBR with simultaneous nitrification and denitrification
Nadeem A Khan1, Simranjeet Singh2, Praveen C Ramamurthy2
1Interdisciplinary Research Center for Membranes and Water Security, King Fahd University of Petroleum and Minerals, Saudi Arabia.
Journal of Environmental Management
|November 17, 2023
Summary
A column-type sequencing batch reactor (SBR) effectively removes nutrients and achieves high simultaneous nitrification and denitrification (SND) rates. This advanced wastewater treatment method enhances extracellular polymeric substances (EPS) for superior nitrogen removal.
Area of Science:
- Environmental Engineering
- Microbiology
- Wastewater Treatment
Background:
- Simultaneous nitrification and denitrification (SND) is crucial for efficient nitrogen removal in wastewater treatment.
- Extracellular polymeric substances (EPS) play a key role in microbial nutrient transformation and removal.
- Column-type sequencing batch reactors (SBRs) offer potential for enhanced biological nutrient removal.
Purpose of the Study:
- To assess the influence and mechanisms of an SBR-based SND system.
- To elucidate the role of functional groups within EPS in nitrogen transformation.
- To evaluate the nutrient and COD removal efficiency of the SBR process.
Main Methods:
- Utilized a column-type sequencing batch reactor (SBR) for wastewater treatment.
- Analyzed extracellular polymeric substances (EPS) composition and properties.
- Employed univariate analysis of variance (ANOVA) and a CatBoost machine learning model.
- Investigated nutrient and chemical oxygen demand (COD) removal efficiencies at varying hydraulic retention times (HRT).
Main Results:
- The SBR process achieved 69% SND efficiency and 66% total nitrogen removal.
- EPS content and nitrogen transport/conversion/retention capacities were enhanced by the SBR.
- Nutrient (88-98%) and COD (93%) removal efficiencies were high within a 6-hour HRT.
- Wastewater concentration and HRT significantly impacted treatment efficiency.
Conclusions:
- The SBR bacterial community is critical for promoting SND.
- The SBR process demonstrates superior performance in nutrient removal and EPS enhancement.
- Post-treatment physicochemical processes may be necessary for complete effluent polishing.
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