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A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities
Published on: December 25, 2015
Bed expansion behavior and sensitivity analysis for super-high-rate anaerobic bioreactor
Xiao-guang Chen1, Ping Zheng, Jing Cai
1Department of Environmental Engineering, Zhejiang University, Hangzhou 310029, China.
Journal of Zhejiang University. Science. B
|January 28, 2010
Summary
This study models super-high-rate anaerobic bioreactor (SAB) bed expansion, finding fluidization is key for stability. Superficial velocities impact bed expansion and sludge contact time, crucial for efficient anaerobic digestion.
Area of Science:
- Environmental Engineering
- Biochemical Engineering
- Chemical Engineering
Background:
- Super-high-rate anaerobic bioreactors (SABs) are advanced systems for wastewater treatment.
- Understanding bed expansion dynamics is critical for optimizing SAB performance and stability.
- Granular sludge washout can destabilize SAB operation.
Purpose of the Study:
- To investigate the bed expansion behavior of SABs.
- To perform a sensitivity analysis of key operational parameters on bed expansion.
- To develop models for predicting bed expansion under different operational states.
Main Methods:
- Established bed expansion behavior models for unfluidization, fluidization, and transportation states.
- Quantified bed expansion ratio (E), maximum bed sludge content (V(pmax)), and maximum bed contact time (tau(max)).
- Analyzed the correlation between superficial gas (ug) and liquid (ul) velocities and bed expansion parameters during stable operation.
Main Results:
- Under fluidization, E ranged from 5.28%-255.69%, V(pmax) from 1,368-4,559 ml, and tau(max) from 104-732 s.
- Bed expansion (E) positively correlated with ug and ul, while V(pmax) and tau(max) negatively correlated.
- Sensitivity analysis showed ug and ul had similar effects on E and V(pmax), but ul had a greater effect on tau(max).
Conclusions:
- The developed models accurately predict SAB bed expansion behavior.
- Fluidization state is essential for stable SAB operation, preventing sludge washout.
- Operational parameters like superficial velocities significantly influence bioreactor efficiency and stability.
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