scispace - formally typeset
Search or ask a question
Topic

Bioreactor

About: Bioreactor is a research topic. Over the lifetime, 9980 publications have been published within this topic receiving 192690 citations. The topic is also known as: bioreactors.


Papers
More filters
Journal ArticleDOI
TL;DR: The SMABR exhibited better results in terms of mixed liquor suspended solids growth, DOC removal,DOC removal, COD removal, transmembrane pressure (TMP) and oxygen uptake rate, while the SMBR showed worse results.

70 citations

Journal ArticleDOI
TL;DR: An improvement in kinetic behaviors for immobilized cells confirms that the fibrous‐bed bioreactor can be used as an effective tool for adapting and screening for acetate‐tolerant strains.
Abstract: The fermentation kinetics of acetic acid production from fructose by Clostridium formicoaceticum was studied at pH 7.6 and 37 degreesC. Recycle batch, fed-batch, and continuous fermentations using immobilized cells in a fibrous-bed bioreactor were studied for their potential application in producing acetic acid from fructose, a fermentable sugar commonly found in corn steep liquor and many other food processing wastes. For the immobilized cell fermentation, acetic acid yield from fructose was approximately 1.0 g/g, with a final acetate concentration of approximately 78 g/L and the overall reactor productivity (based on the fibrous bed bioreactor volume) of approximately 0.95 g/(L.h) in the fed-batch fermentation. For a similar fed-batch fermentation with free cells, acetic acid yield was approximately 0.9 g/g, the highest final acetate concentration was approximately 46 g/L, and the overall productivity was approximately 0.12 g/(L.h). In the continuous fermentation with immobilized cells, the reactor productivity decreased from 3.2 to 1. 3 g/(L.h) as retention time increased from 16 to 72 h to reach 100% conversion. Compared to free-cell fermentations, the superior performance of the fibrous-bed bioreactor can be attributed to the high density (>30 g/L) of viable cells immobilized in the fibrous bed. The fermentation product, acetic acid, was found to be a noncompetitive inhibitor to the cells. However, the immobilized cells had a higher maximum production rate (pmax) and a higher value for the inhibition rate constant (Kp) than those for the free cells, suggesting that the immobilized cells in the fibrous-bed bioreactor were less sensitive to acetic acid inhibition than the free cells. This improvement in kinetic behaviors for immobilized cells confirms that the fibrous-bed bioreactor can be used as an effective tool for adapting and screening for acetate-tolerant strains.

70 citations

01 Oct 1981
TL;DR: In this article, an experiment using an activated carbon filter for the treatment of phenol-bearing wasterwater from coal gasification processes is discussed, and two granular-activated-carbon-packed anaerobic filter systems were constructed for use in the study.
Abstract: An experiment using an activated carbon filter for the treatment of phenol-bearing wasterwater from coal gasification processes is discussed. Two granular-activated-carbon-packed anaerobic filter systems were constructed for use in the study. Both phenol and glucose of phenol-fed reactor systems were operated under continuous feeding for a period of 735 days. The glucose-fed reactor was very effective in reducing the organic content of the feed substrate. The performance of the phenol-fed reactor was tested at three different phenol concentration levels: (1) 200 mg/l; (2) 400 mg/l; and (3) 1000 mg/l. Using the 200 mg/l concentration of phenol an average 79% of the feed chemical oxygen demand (COD) was accounted for in the aqueous and gaseous phases of the final effluent. Using 400 mg/l the COD accounted for the aqueous and gaseous phases of the effluent rose to an average of 92%, and using 1000 mg/l, the COD removal efficiencies from the three columns fell to an average of 90%, respectively. Despite the differences in removal efficiencies between the different phases of the experiment, the granular-activated-carbon-packed anaerobic bioreactor proved to be an effective process in the reduction of phenol from a synthetically prepared wastewater. In addition to phenol reduction, there was alsomore » a consistent and effective reduction of the chemical oxygen demand and the total organic carbon content of the waste at a time when a methane-rich gaseous by-product was being produced simultaneously.« less

70 citations

Journal ArticleDOI
TL;DR: Anaerobic co-digestion of food waste and biosolids was carried out in sequential batch and single-stage batch systems in four treatments and methane generation rate was significantly correlated to the community structure of Bacteria but not Archaea, indicating that the substrates that are produced by acetogens (Bacteria) are important for the growth andcommunity structure of the methanogens (Archaea).
Abstract: Anaerobic co-digestion of food waste and biosolids was carried out in sequential batch and single-stage batch systems in four treatments. Methane yield, which was used as a functional process parameter, differed between treatments, with the single-stage batch system generating lower volumes than the sequential batch systems. Volatile fatty acid (VFA) concentrations and pH in the leachate also differed between treatments. VFA concentrations were highest and methane generation yields lowest in the single-stage batch system in comparison to the sequential batch systems. The anaerobic microbial community structure of the domains Archaea and Bacteria, determined by denaturing gradient gel electrophoresis, differed between treatments and was correlated to a number of environmental parameters such as pH, VFA concentration and methane generation rate. Methane generation rate was significantly correlated to the community structure of Bacteria but not Archaea. This indicated that the substrates that are produced by acetogens (Bacteria) are important for the growth and community structure of the methanogens (Archaea). Community structure of Archaea changed over time, but this had no observable effect on functional ability based on methane yields. Microbial diversity (H') was shown to be not important in developing a functionally successful anaerobic microbial community.

70 citations

Journal ArticleDOI
TL;DR: An advanced version of a two-compartment scale-down bioreactor that simulates inhomogeneities present in large-scale industrial bioreactors on the laboratory scale is described, found that oscillating substrate and DO concentration led to diminished glucose uptake, ethanol formation and an altered amino acid synthesis.
Abstract: This study describes an advanced version of a two-compartment scale-down bioreactor that simulates inhomogeneities present in large-scale industrial bioreactors on the laboratory scale. The system is made of commercially available parts and is suitable for sterilization with steam. The scale-down bioreactor consists of a usual stirred tank bioreactor (STR) and a plug flow reactor (PFR) equipped with static mixer modules. The PFR module with a working volume of 1.2 L is equipped with five sample ports, and pH and dissolved oxygen (DO) sensors. The concept was applied using the non-sporulating Bacillus subtilis mutant strain AS3, characterized by a SpoIIGA gene knockout. In a fed-batch process with a constant feed rate, it is found that oscillating substrate and DO concentration led to diminished glucose uptake, ethanol formation and an altered amino acid synthesis. Sampling at the PFR module allowed the detection of dynamics at different concentrations of intermediates, such as pyruvic acid, lactic acid and amino acids. Results indicate that the carbon flux at excess glucose and low DO concentrations is shifted towards ethanol formation. As a result, the reduced carbon flux entering the tricarboxylic acid cycle is not sufficient to support amino acid synthesis following the oxaloacetic acid branch point.

70 citations


Network Information
Related Topics (5)
Wastewater
92.5K papers, 1.2M citations
84% related
Fermentation
68.8K papers, 1.2M citations
82% related
Biofuel
23.8K papers, 902.4K citations
81% related
Activated carbon
39.6K papers, 920K citations
80% related
Freundlich equation
27.6K papers, 941.4K citations
80% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
20241
2023726
20221,549
2021388
2020401
2019413