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Medium Preparation for the Cultivation of Microorganisms under Strictly Anaerobic/Anoxic Conditions
Published on: August 15, 2019
Fermentative biohydrogen production from lactate and acetate
Chao-Wei Wu1, Liang-Ming Whang, Hai-Hsuan Cheng
1Department of Environmental Engineering, National Cheng Kung University, No. 1, University Road, Tainan 701, Taiwan.
Bioresource Technology
|February 10, 2012
Summary
This study optimized fermentative hydrogen production using a continuous-flow stirred tank reactor (CSTR) with lactate and acetate. Clostridium tyrobutyricum was identified as the key hydrogen-producing bacteria under optimal volumetric loading rates.
Area of Science:
- Biotechnology
- Environmental Science
- Microbiology
Background:
- Optimizing microbial hydrogen production is crucial for sustainable energy.
- Lactate and acetate are promising substrates for fermentative hydrogen generation.
- Continuous-flow stirred tank reactors (CSTRs) offer potential for efficient bioprocesses.
Purpose of the Study:
- To enrich hydrogen-producing bacteria using a CSTR fed with lactate and acetate.
- To determine the optimal operating conditions for fermentative hydrogen production.
- To identify the dominant bacterial species responsible for hydrogen generation.
Main Methods:
- Operation of a CSTR with varying substrate concentrations and hydraulic retention times (HRT).
- Determination of optimal volumetric loading rate (VLR) for hydrogen production.
- Batch experiments to analyze electron (e(-)) equivalence distribution for cell growth and hydrogen production.
- Cloning and sequencing to identify the microbial community composition.
Main Results:
- An optimal VLR of 55.64 kg-COD/m(3)/day was identified for hydrogen production.
- Lower VLR favored cell growth, while higher VLR promoted hydrogen production.
- Wash-out of bacteria was observed at lower HRT with high substrate concentrations.
- Clostridium tyrobutyricum was identified as the predominant hydrogen-producing bacterium.
Conclusions:
- The study successfully enriched a hydrogen-producing bacterial culture using a CSTR.
- Optimal VLR and HRT are critical for maximizing fermentative hydrogen production.
- Understanding substrate concentration limits and bacterial dynamics is essential for process stability.
- Clostridium tyrobutyricum plays a significant role in hydrogen generation from lactate and acetate.
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