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Updated: Feb 8, 2026
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A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities
Published on: December 25, 2015
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[Nitrogen Removal Performance and Microbial Community Analysis of Activated Sludge Immobilization].
Xiao-Yi Xu1,2, Xiao-Lu You1,2, Chen-Pei Lü1,2
1College of Urban Construction and Environmental Engineering, Chongqing University, Chongqing 400045, China.
Huan Jing Ke Xue= Huanjing Kexue
|July 3, 2018
Summary
Immobilized activated sludge in embedding beads effectively removes nitrogen from wastewater. This method enhances microbial communities for efficient biological denitrification, offering a novel approach to wastewater treatment.
Area of Science:
- Environmental Microbiology
- Water Treatment Engineering
- Biotechnology
Background:
- Secondary effluent often contains residual nitrogen, necessitating further treatment to prevent eutrophication.
- Biological nitrogen removal is crucial for meeting stringent wastewater discharge standards.
- Immobilization techniques offer potential for enhancing microbial activity and stability in bioreactors.
Purpose of the Study:
- To investigate the efficacy of immobilized activated sludge for enhanced nitrogen removal from secondary effluent.
- To characterize the microbial community structure within embedding beads.
- To explore the potential of novel biological denitrification pathways.
Main Methods:
- Intermittent sequencing batch reactor (ISBR) experiments were conducted using synthetic wastewater.
- Activated sludge was immobilized in porous embedding beads.
- Nitrogen removal efficiency, microbial community structure (high-throughput sequencing), and scanning electron microscopy (SEM) were analyzed.
- Key operational parameters like packing ratio, temperature, dissolved oxygen (DO), and chemical oxygen demand (COD) were controlled.
Main Results:
- Maximum total nitrogen removal loads ranged from 7.78 to 23.18 mg·(L·h)⁻¹ under optimal conditions.
- SEM confirmed embedding beads as porous, ideal support materials with adhered microorganisms.
- High-throughput sequencing revealed significant shifts in microbial communities within the beads, favoring denitrifying bacteria.
- Microorganisms capable of heterotrophic nitrification and aerobic denitrification were identified.
Conclusions:
- Immobilized activated sludge in embedding beads is a highly effective method for advanced nitrogen removal.
- The unique microenvironment within the beads supports a robust microbial community conducive to denitrification.
- The identified microorganisms and pathways offer potential for developing innovative biological denitrification strategies.
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