{"title":"Pros and cons of airlift and bubble column bioreactors: How internals improve performance","authors":"","doi":"10.1016/j.bej.2024.109539","DOIUrl":null,"url":null,"abstract":"<div><div>Gas fermentation is a promising technology of high commercial interest, particularly for capturing CO<sub>2</sub> and CO from industrial off-gases to reduce greenhouse gas emissions and replace fossil fuels for bulk chemical production. Therefore, evaluating promising bioreactor settings <em>ab initio</em> is a crucial step. Whereas alternate configurations may be tested in laborious scale up studies, the procedure may be accelerated by <em>in silico</em> studies that accompany or even partially replace wet-lab work once the models are validated. In this context, the current study compares various pneumatically agitated reactor types – bubble column reactor (BCR), annulus- and center-rising internal-loop airlift reactor (AR-IL-ALR and CR-IL-ALR), and external-loop airlift reactor (EL-ALR) – to identify advantages and disadvantages for the given application based on computational fluid dynamics (CFD) models. Process performance is optimized by introducing internal structures to guide the flow. Despite a significant increase in the mass transfer coefficient (<span><math><mrow><msub><mrow><mi>k</mi></mrow><mrow><mi>L</mi></mrow></msub><mi>a</mi></mrow></math></span>) through internal modifications, the CR-IL-ALR still exhibited the poorest performance. The optimized AR-IL-ALR demonstrated good mixing and, after introducing an open-cone shaped internal in the head part and a conical bottom, superior mass transfer, achieving an enhancement over 10 % in the mass transfer coefficient to 315 1/h. This study thereby outlines the potential of internal structures for process improvement, as well as the value of <em>a priori in silico</em> design of reactor configurations.</div></div>","PeriodicalId":8766,"journal":{"name":"Biochemical Engineering Journal","volume":null,"pages":null},"PeriodicalIF":3.7000,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Biochemical Engineering Journal","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1369703X24003267","RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"BIOTECHNOLOGY & APPLIED MICROBIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Gas fermentation is a promising technology of high commercial interest, particularly for capturing CO2 and CO from industrial off-gases to reduce greenhouse gas emissions and replace fossil fuels for bulk chemical production. Therefore, evaluating promising bioreactor settings ab initio is a crucial step. Whereas alternate configurations may be tested in laborious scale up studies, the procedure may be accelerated by in silico studies that accompany or even partially replace wet-lab work once the models are validated. In this context, the current study compares various pneumatically agitated reactor types – bubble column reactor (BCR), annulus- and center-rising internal-loop airlift reactor (AR-IL-ALR and CR-IL-ALR), and external-loop airlift reactor (EL-ALR) – to identify advantages and disadvantages for the given application based on computational fluid dynamics (CFD) models. Process performance is optimized by introducing internal structures to guide the flow. Despite a significant increase in the mass transfer coefficient () through internal modifications, the CR-IL-ALR still exhibited the poorest performance. The optimized AR-IL-ALR demonstrated good mixing and, after introducing an open-cone shaped internal in the head part and a conical bottom, superior mass transfer, achieving an enhancement over 10 % in the mass transfer coefficient to 315 1/h. This study thereby outlines the potential of internal structures for process improvement, as well as the value of a priori in silico design of reactor configurations.
期刊介绍:
The Biochemical Engineering Journal aims to promote progress in the crucial chemical engineering aspects of the development of biological processes associated with everything from raw materials preparation to product recovery relevant to industries as diverse as medical/healthcare, industrial biotechnology, and environmental biotechnology.
The Journal welcomes full length original research papers, short communications, and review papers* in the following research fields:
Biocatalysis (enzyme or microbial) and biotransformations, including immobilized biocatalyst preparation and kinetics
Biosensors and Biodevices including biofabrication and novel fuel cell development
Bioseparations including scale-up and protein refolding/renaturation
Environmental Bioengineering including bioconversion, bioremediation, and microbial fuel cells
Bioreactor Systems including characterization, optimization and scale-up
Bioresources and Biorefinery Engineering including biomass conversion, biofuels, bioenergy, and optimization
Industrial Biotechnology including specialty chemicals, platform chemicals and neutraceuticals
Biomaterials and Tissue Engineering including bioartificial organs, cell encapsulation, and controlled release
Cell Culture Engineering (plant, animal or insect cells) including viral vectors, monoclonal antibodies, recombinant proteins, vaccines, and secondary metabolites
Cell Therapies and Stem Cells including pluripotent, mesenchymal and hematopoietic stem cells; immunotherapies; tissue-specific differentiation; and cryopreservation
Metabolic Engineering, Systems and Synthetic Biology including OMICS, bioinformatics, in silico biology, and metabolic flux analysis
Protein Engineering including enzyme engineering and directed evolution.