Volumetric mass transfer coefficient in the fermenter agitated by Rushton turbines of various diameters in viscous batch

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22340%2F17%3A43914700" target="_blank" >RIV/60461373:22340/17:43914700 - isvavai.cz</a>

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Volumetric mass transfer coefficient in the fermenter agitated by Rushton turbines of various diameters in viscous batch

Popis výsledku v původním jazyce

In cases of aerobic fermentations, the apparatuses for their industrial performance are designed also from the viewpoint of sufficient oxygen supply to avoid oxygen limitation of biomass, i.e. to provide sufficient oxygen gas-liquid transfer rate. For biochemical processes with high respiration rate, the oxygen demand of which is also high, mechanically agitated vessels are usually used. In comparison with airlift reactors and bubble columns, these equipments enable to reach higher oxygen gas-liquid transfer rates, i.e., they reach higher values of volumetric mass transfer coefficient, kLa. Due to the hydrodynamic complexity of mechanically agitated gas-liquid systems, the kLa predictions from first principles are not reliable yet, and, therefore, experimental data are needed for rational design of fermenters. Most fermentation broths are of increased viscosity, for which the lack of reliable kLa data exists due to the limitations of most measurement methods. We recently suggested and verified the methodology to obtain reliable experimental kLa data in viscous batch even for high dissipated energies. We used the dynamic pressure method (DPM), the experimental set-up of which was modified for the measurement in viscous batch. In our previous work, we provided fairly large kLa database to establish suitable correlation shapes to describe kLa dependencies on process conditions in viscous liquids. Now, we focused on the effect of impeller diameter on transport characteristics because in cases of shear stress sensitive biomass this parameter strongly affects the fermentation efficiency. The measurements were conducted in multiple-impeller fermenters, both of laboratory and of pilot-plant scale, using viscous Newtonian batch under a wide range of experimental conditions (impeller frequencies, gas flow-rates, impeller diameters).

Název v anglickém jazyce

Volumetric mass transfer coefficient in the fermenter agitated by Rushton turbines of various diameters in viscous batch

Popis výsledku anglicky

In cases of aerobic fermentations, the apparatuses for their industrial performance are designed also from the viewpoint of sufficient oxygen supply to avoid oxygen limitation of biomass, i.e. to provide sufficient oxygen gas-liquid transfer rate. For biochemical processes with high respiration rate, the oxygen demand of which is also high, mechanically agitated vessels are usually used. In comparison with airlift reactors and bubble columns, these equipments enable to reach higher oxygen gas-liquid transfer rates, i.e., they reach higher values of volumetric mass transfer coefficient, kLa. Due to the hydrodynamic complexity of mechanically agitated gas-liquid systems, the kLa predictions from first principles are not reliable yet, and, therefore, experimental data are needed for rational design of fermenters. Most fermentation broths are of increased viscosity, for which the lack of reliable kLa data exists due to the limitations of most measurement methods. We recently suggested and verified the methodology to obtain reliable experimental kLa data in viscous batch even for high dissipated energies. We used the dynamic pressure method (DPM), the experimental set-up of which was modified for the measurement in viscous batch. In our previous work, we provided fairly large kLa database to establish suitable correlation shapes to describe kLa dependencies on process conditions in viscous liquids. Now, we focused on the effect of impeller diameter on transport characteristics because in cases of shear stress sensitive biomass this parameter strongly affects the fermentation efficiency. The measurements were conducted in multiple-impeller fermenters, both of laboratory and of pilot-plant scale, using viscous Newtonian batch under a wide range of experimental conditions (impeller frequencies, gas flow-rates, impeller diameters).

Druh

D - Stať ve sborníku

CEP obor

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OECD FORD obor

20401 - Chemical engineering (plants, products)

Projekt

<a href="/cs/project/GA15-21715S" target="_blank" >GA15-21715S: Experimentální studie přenosu hmoty kapalina-plyn za přítomnosti pevných částis a ve viskózní vsádce</a><br>

Návaznosti

S - Specificky vyzkum na vysokych skolach

Rok uplatnění

2017

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název statě ve sborníku

PROCEEDINGS 44th International Conference of the Slovak Society of Chemical Engineering

ISBN

978-80-89597-58-1

ISSN

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e-ISSN

neuvedeno

Počet stran výsledku

10

Strana od-do

784-793

Název nakladatele

Slovak Society of Chemical Engineering

Místo vydání

Bratislava

Místo konání akce

Demänovská dolina

Datum konání akce

22. 5. 2017

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

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