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Novel separate aeration self-circulating technology for continuous aerobic granular sludge process: Performance
Wei-Kang Qi1, Run-Feng Tian1, Bo Li1
1National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China.
Water Research
|July 13, 2024
Summary
A novel Zier technology enhances continuous aerobic granular sludge (AGS) processes for wastewater treatment. This method optimizes reactor design and control for efficient pollutant removal and nitrogen capacity.
Area of Science:
- Environmental Engineering
- Wastewater Treatment Technologies
- Bioreactor Design
Background:
- Continuous aerobic granular sludge (AGS) processes offer potential for upgrading wastewater treatment plants.
- Current AGS processes face challenges due to complex structures and operations.
Purpose of the Study:
- To evaluate the feasibility, optimization, and control strategy of a novel separate aeration self-circulating technology (Zier) for AGS cultivation.
- To address the operational complexities of existing AGS systems.
Main Methods:
- Computational fluid dynamics (CFD) simulations.
- Theoretical calculations.
- Experimental validation.
- Reactor design optimization (aeration column diameter, height/diameter ratio, circulation pipe diameter).
Main Results:
- An optimal superficial gas velocity of 1.3 cm/s was identified for efficient pollutant removal and sludge granulation.
- Optimized reactor dimensions significantly increased nitrogen removal capacity to over 1.6 kg N/m³d.
- A consistent flow regime for granulation was achieved using a smaller circulation pipe diameter.
- Integration of multiple CSTRs and PFRs within the Zier reactor was demonstrated.
Conclusions:
- The Zier reactor demonstrates superior performance and efficiency for continuous AGS processes.
- The proposed multi-scenario control strategy provides a roadmap for Zier reactor operation.
- This technology offers valuable insights for advancing efficient wastewater treatment.
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