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A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities
Published on: December 25, 2015
Effect of membrane bioreactor configurations on sludge structure and microbial activity
1Laboratoire de Modélisation, Mécanique et Procédés Propres (M2P2), UMR 6181, Université Paul Cézanne Aix-Marseille 3, Europôle de l'Arbois, Bât Laennec hall C BP 80, 13545 Aix-en-provence cedex 4, France.
Bioresource Technology
|October 16, 2010
Summary
The immersed membrane bioreactor (MBR) configuration better supports autotrophic microbes, while the external MBR enhances heterotrophic microbial development and releases more soluble microbial products.
Area of Science:
- Environmental Engineering
- Biotechnology
Background:
- Membrane bioreactors (MBRs) are crucial for wastewater treatment.
- Understanding the impact of MBR configuration on sludge characteristics is vital for optimizing performance.
Purpose of the Study:
- To compare the effects of external and immersed MBR configurations on activated sludge (AS) structure and microbial activity.
- To investigate how MBR design influences sludge deflocculation, soluble microbial product (SMP) release, and microbial community development.
Main Methods:
- Sludge structure analysis using rheological measurements.
- Quantification of soluble microbial products (SMP).
- Respirometry tests to assess microbial activity (heterotrophic and autotrophic).
Main Results:
- External MBRs induced higher shear stress, leading to decreased viscosity and AS deflocculation.
- Higher SMP release (5 mgCOD gMLVSS(-1)) was observed in external MBRs compared to immersed MBRs (2 mgCOD gMLVSS(-1)).
- Immersed MBRs facilitated easier autotrophic microbe development, whereas external MBRs promoted better heterotrophic microbe development.
Conclusions:
- MBR configuration significantly impacts sludge properties and microbial activity.
- Immersed MBRs offer advantages for autotrophic processes, while external MBRs may be better suited for heterotrophic processes.
- Rheological properties and SMP release are key indicators of MBR performance influenced by configuration.
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