Measurement of gas and liquid flows in stirred tank reactors with multiple agitators

Manikowski, M.; Bodemeier, Steffen; Lübbert, Α.; Bujalski, W.; Nienow, Alvin W.

doi:10.1002/cjce.5450720502

Cited by 36 publications

(6 citation statements)

References 15 publications

(15 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Given that we are working at surfactant concentrations well below the critical micelle conentration (CMC), it was important to use a low shear agitator like the hydrofoil in order to avoid shear-induced particle coagulation. [21] Several batch polymerizations were run to explore the impact of the agitation system and speed on the polymerization rate and the reactor temperature. The results are shown in Figure 3 for the original S1 configuration, where it can be seen that the agitation rate has a strong impact on the rate of batch polymerization (Figure 3A), and on the ability to control the reactor temperature (Figure 3C).…”

Section: Influence Of Agitation On the Reactionmentioning

confidence: 99%

Emulsion polymerization of vinylidene fluoride: Effects of mixing and reaction conditions on the initial rate of polymerization

Ecoscia¹,

McKenna²,

Ecoscia³

et al. 2021

Can J Chem Eng

View full text Add to dashboard Cite

In order to contribute to a better understanding of the emulsion polymerization of vinylidene fluoride (VDF) an experimental study under conditions of temperature and pressure similar to those found in industrial processes was carried out. It is shown that the initial rate of polymerization is strongly influenced by the agitation of the reactor, with the rate of reaction increasing as the rate of agitation increases. In addition, using a more efficient impeller also increases the polymerisation. It is proposed that this is due to mass transfer limitations. This idea is confirmed by a similar dependence of the average molecular weight on agitation. Experimental data also shows that particles are formed by homogeneous coagulative nucleation. It is proposed that particle nucleation occurs throughout the polymerisation, and that a competition between controlled coagulation and particle generation governs the rate of reaction.

show abstract

Section: Influence Of Agitation On the Reactionmentioning

confidence: 99%

Emulsion polymerization of vinylidene fluoride: Effects of mixing and reaction conditions on the initial rate of polymerization

Ecoscia¹,

McKenna²,

Ecoscia³

et al. 2021

Can J Chem Eng

View full text Add to dashboard Cite

show abstract

“…The blend time is the time needed to reach a certain degree of homogeneity across all probes and the blend time may be function of the number of probes . Global methods are non‐intrusive and attempt to identify unmixed zones , . They need to be carried out in transparent vessels and use a fast chemical reaction to track mixing.…”

Section: Introductionmentioning

confidence: 99%

Blend Time Measurement in the Confined Impeller Stirred Tank

et al. 2019

View full text Add to dashboard Cite

An image processing technique is applied to measure the blend time in a confined impeller stirred tank (CIST). An acid-base reaction is used to track mixing. The blend time is defined as the time taken to 95 % or 99 % of the pixels change color from purple to yellow. Six sets of impellers are employed: Rushtons, A310s, pitched-blade turbines (PBTs; three different combinations of up-and downpumping), and Intermigs. Variation of the Reynolds number Re showed that the blend time becomes shorter with increasing Re and longer with higher viscosity. As Re drops below 225, compartmentalization becomes apparent and the decolorization percentage increases suddenly when the acid reaches each communication point between the impellers.

show abstract

“…Se sabe también que con los impulsores axiales se ha obtenido mejor producción de blastosporas que con los impulsores radiales, esto debido a que el mezclado de los primeros permite una distribución de temperaturas similar en todas las partes del líquido de fermentación (Manikowski et al, 1994;Jaworski et al, 1998;Sardeing et al, 2004).…”

Section: Introductionunclassified

Estudio de las condiciones de mezclado en fermentador para la producción de blastosporas de Beauveria bassiana

García-Gutiérrez¹,

González-Maldonado²,

Medrano-Roldán³

et al. 2013

Rev. Colomb. Biotecnol.

View full text Add to dashboard Cite

Estudio de las condiciones de mezclado en fermentador para la producción de ResumenSe caracterizaron tres fermentadores: New Brunswick M-19 de 14 litros, Applikon Biocontroller 1035 de 7 litros y New Brunswick Bioflo III de 7 litros, determinando el coeficiente volumétrico de transferencia de oxígeno (KLa), la retención de gas (RG) y el tiempo de mezclado (tM). El fermentador New Brunswick Bioflo III tuvo los mejores valores con una relación de diámetro del impulsor/diámetro del tanque (DI/DT) de 0.43, KLa = 9.5-208 h -1 y tM = 1.0-3.0 s, por lo que fue seleccionado para realizar la producción de blastosporas de Beauveria bassiana, utilizando melaza como fuente de carbono. Se estudiaron las condiciones de mezclado, utilizando diferentes combinaciones de impulsores tipo Rushton, Maxflo y Lightnin, bajo un diseño experimental factorial 3 2 . El tiempo de propagación fue de 4 días, el volumen de trabajo 4 litros, 10% de inóculo (1x10 6 blastosporas/ml), temperatura 30°C, agitación de 400-500 rpm, aireación de 0.5-1.0 vvm, y pH de 5.4.El hongo se desarrolló mejor utilizando la combinación de impulsores Rushton-Maxflo a 400 rpm y 1.0 vvm (F = 10.324, p ≤ 0.0123) (DMS=0.585), obteniendo una concentración de 1.2x10 9 blastosporas/ml, 2.2 g/l de biomasa y 2.48 g/l de consumo de sustrato (Y x/s=0.89). Las condiciones de mezclado y los parámetros obtenidos pueden ser aplicados en otros fermentadores para optimizar la producción de blastosporas de B. bassiana en la elaboración experimental de bioinsecticidas.Palabras clave: fermentación líquida, aireación, agitación, hongo entomopatógeno. AbstractIn this work three fermenters were characterized: New Brunswick M-19 of 14 liters, Biocontroller Applikon 1035 of 7 liters and New Brunswick Bioflo III of 7 liters, determining the volumetric coefficient oxygen transfer (KLa), gas hold up (GH) and the mixing time (tM). The fermenter New Brunswick Bioflo III had the best values with a ratio of diameter of the impeller/ vessel (DI/DT) of 0.43, KLa = 9.5-208 h -1 and tM = 1.0-3.0 s, so it was selected for the production of blastospores of Beauveria bassiana, using molasses as carbon source. We studied the mixing conditions, using different combinations of impellers, type Rushton, Lightnin and Maxflo under a factorial experimental design 3 2 . The propagation time was of 4 days, working volume 4l, 10% inoculum (1x10 6 blastospores/ml), temperature 30°C, agitation of 400-500 rpm, aeration 0.5-1.0 vvm, and pH of 5.4. The fungus growth better using a combination of impellers Rushton-Maxflo at 400 rpm and 1.0 vvm (F = 10.324, p ≤ 0.0123) (LSD = 0.585) obtaining a concentration of 1.2x10 9 blastospores/ml, 2.2 g/l biomass and 2.48 g/l of substrate consumption (Y x/s = 0.89). The mixing conditions and the parameters obtained can be applied to optimize the blastospore productions of B. bassiana to fermenter level in the experimental production of bioinsecticides.

show abstract

Measurement of gas and liquid flows in stirred tank reactors with multiple agitators

Cited by 36 publications

References 15 publications

Emulsion polymerization of vinylidene fluoride: Effects of mixing and reaction conditions on the initial rate of polymerization

Emulsion polymerization of vinylidene fluoride: Effects of mixing and reaction conditions on the initial rate of polymerization

Blend Time Measurement in the Confined Impeller Stirred Tank

Estudio de las condiciones de mezclado en fermentador para la producción de blastosporas de Beauveria bassiana

Contact Info

Product

Resources

About