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In Seop Chang - One of the best experts on this subject based on the ideXlab platform.
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determination of volumetric gas liquid Mass Transfer coefficient of carbon monoxide in a batch cultivation system using kinetic simulations
Bioresource Technology, 2017Co-Authors: Nulee Jang, Muhammad Yasin, Robert W Lovitt, Shinyoung Park, In Seop ChangAbstract:Abstract A mathematical model of microbial kinetics was introduced to predict the overall volumetric gas–liquid Mass Transfer coefficient ( k L a ) of carbon monoxide (CO) in a batch cultivation system. The cell concentration ( X ), acetate concentration ( C ace ), headspace gas ( N co and N co 2 ), dissolved CO concentration in the fermentation medium ( C co ), and Mass Transfer Rate ( R ) were simulated using a variety of k L a values. The simulated results showed excellent agreement with the experimental data for a k L a of 13/hr. The C co values decreased with increase in cultivation times, whereas the maximum Mass Transfer Rate was achieved at the mid-log phase due to vigorous microbial CO consumption Rate higher than R . The model suggested in this study may be applied to a variety of microbial systems involving gaseous substRates.
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enhanced Mass Transfer Rate of methane via hollow fiber membrane modules for methylosinus trichosporium ob3b fermentation
Journal of Industrial and Engineering Chemistry, 2016Co-Authors: Nulee Jang, Muhammad Yasin, In Seop ChangAbstract:Abstract Polyvinylidine fluoride (PVDF) hollow fiber membranes were employed to enhance Mass Transfer Rate of methane in water for the fermentation of Methylosinus trichosporium OB3b. Compared to common alumina bubbler, hollow fiber membrane modules (HFMMs) afforded smaller methane bubble size and larger methane–water volumetric Mass Transfer coefficient (kLa) as high as 150.1 h−1. Furthermore, cell growth Rate and maximum optical density of M. trichosporium OB3b were increased by 67.3 and 77.4%, respectively, by adapting forty HFMMs, compared to those of alumina bubbler.
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effect of co partial pressure on cell recycled continuous co fermentation by eubacterium limosum kist612
Process Biochemistry, 2001Co-Authors: In Seop Chang, Byung Hong Kim, Robert W Lovitt, Joon Seoung BangAbstract:Eubacterium limosum KIST612 was cultivated on carbon monoxide using a cell-recycled continuous fermentation system to produce organic acids. A bubble column reactor system (kLa=72 h−1) was used with a membrane to allow on-line products removal with cell recycle. When cell concentration reached 5.25 g l−1 in the reactor, the cell concentration did not increase at carbon monoxide (CO) partial pressures lower than 74 kPa though CO was consumed with the acidic products formation. At this stage, the overall CO Mass Transfer Rate (kLa[C*−CL]) was lower than required for the maximum cell growth (qCOmaxX), but higher than that to meet the maintenance requirement (msX). When the CO Mass Transfer Rate was maintained higher than maintenance requirement by increasing CO partial pressure, the cell concentration increased to 9.5 g l−1.
Angel Irabien - One of the best experts on this subject based on the ideXlab platform.
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carbon dioxide capture from flue gases using a cross flow membrane contactor and the ionic liquid 1 ethyl 3 methylimidazolium ethylsulfate
Industrial & Engineering Chemistry Research, 2010Co-Authors: Jonathan Albo, Patricia Luis, Angel IrabienAbstract:Carbon dioxide (CO2) emissions have to be controlled and reduced in order to avoid environmental risks. Membrane processes in combination with the use of ionic liquids are recently under research and development in order to demonstRate a zero solvent emission process for CO2 capture. In this work, the application of a cross-flow membrane contactor is studied for CO2 absorption when the ionic liquid 1-ethyl-3-methylimidazolium ethylsulfate is used as solvent. A mathematical model considering a parallel flow configuration is applied for a cross-flow system in order to describe the Mass Transfer Rate. At a macroscopic level, Koveralla is calculated considering different mixing models corresponding to plug flow and continuous stirred models and a first order Mass Transfer Rate. A microscopic model based on laminar flow has been applied, obtaining a membrane Mass Transfer coefficient of km = 3.78 × 10−6 m·s−1, which is about five times higher than that obtained in the macroscopic model. The interfacial area, a...
Jonathan Albo - One of the best experts on this subject based on the ideXlab platform.
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carbon dioxide capture from flue gases using a cross flow membrane contactor and the ionic liquid 1 ethyl 3 methylimidazolium ethylsulfate
Industrial & Engineering Chemistry Research, 2010Co-Authors: Jonathan Albo, Patricia Luis, Angel IrabienAbstract:Carbon dioxide (CO2) emissions have to be controlled and reduced in order to avoid environmental risks. Membrane processes in combination with the use of ionic liquids are recently under research and development in order to demonstRate a zero solvent emission process for CO2 capture. In this work, the application of a cross-flow membrane contactor is studied for CO2 absorption when the ionic liquid 1-ethyl-3-methylimidazolium ethylsulfate is used as solvent. A mathematical model considering a parallel flow configuration is applied for a cross-flow system in order to describe the Mass Transfer Rate. At a macroscopic level, Koveralla is calculated considering different mixing models corresponding to plug flow and continuous stirred models and a first order Mass Transfer Rate. A microscopic model based on laminar flow has been applied, obtaining a membrane Mass Transfer coefficient of km = 3.78 × 10−6 m·s−1, which is about five times higher than that obtained in the macroscopic model. The interfacial area, a...
J.c. Schouten - One of the best experts on this subject based on the ideXlab platform.
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Effect of the foam stirrer design on the catalytic performance of rotating foam stirrer reactors
2020Co-Authors: M A Leon, J Van Der Schaaf, T A Nijhuis, P Geers, J.c. SchoutenAbstract:h i g h l i g h t s " Rotating foam stirrer reactors have promising applications for multiphase processes. " Enhanced liquid-solid Mass Transfer due to the fast catalyst surface refreshment. " Foam stirrer design has a strong influence on the liquid-solid Mass Transfer Rate. " Higher Mass Transfer Rates than in a slurry reactor can be achieved. " Same production Rate as in the slurry reactor obtained using 62% less catalyst. a r t i c l e i n f o The liquid-solid Mass Transfer Rate in a rotating foam stirrer reactor and in a slurry reactor is studied using the hydrogenation of styrene as a model reaction. The rotating foam stirrer reactor is a novel type of multi-phase reactor where highly open-celled materials, solid foams, are used as a catalyst support and as a stirrer. The design of the foam stirrer has a strong influence on the liquid-solid Mass Transfer Rate. Using a donut-shaped foam block configuration, the liquid solid Mass Transfer coefficient, k LS , is five times lower than in a blade configuration. The reduced liquid circulation through the foam block structure is explained by a higher frictional pressure drop. The pore Reynolds number indicates that the flow is in the laminar regime for the foam block stirrer while it is turbulent for the blade stirrer. Local measurements of k LS indicate a Mass Transfer profile along the height of the foam block structure, allowing a pertinent choice of the catalyst location within the foam block and/or suggesting changes of the foam block design to avoid the bottom effects, for instance, using a conical foam block shape. However, the foam block stirrer offers higher liquid-solid interfacial area than a blade stirrer, resulting in higher k LS a LS . At a power input above 1000 W=m 3 L and using a 20 ppi foam block with the top part catalytically active, the reaction Rate is not liquid-solid Mass Transfer limited. Compared to a Rushton stirrer, the liquid-solid Mass Transfer Rate is enhanced because of a high liquid-solid interfacial area and a fast refreshment of the catalyst surface. k LS a LS values of 0.5 s À1 are obtained compared to 0.04 s À1 for the slurry system. The same production Rate as in the slurry reactor is achieved using 62% less catalyst. As the catalyst is immobilized on the stirrer, an additional advantage of the rotating foam stirrer reactor is the absence of a catalyst separation step. Attrition and agglomeration of the catalyst do not occur and the foam catalyst can be reused
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liquid liquid Mass Transfer in a rotor stator spinning disc reactor
Chemical Engineering Journal, 2012Co-Authors: F. Visscher, John Van Der Schaaf, Mart H J M De Croon, J.c. SchoutenAbstract:Abstract This paper presents the liquid–liquid flow behaviour and the liquid–liquid Mass Transfer Rates for a rotor–stator spinning disc reactor, with an axial disc spacing of 1 mm, a rotor radius of 0.066 m, and rotational disc speeds up to 1600 rpm. The liquid–liquid Mass Transfer Rate is determined from extraction experiments of benzoic acid from n -heptane to water. For the calculation of the overall Mass Transfer Rate the dimerization and acid dissociation equilibria are taken into account. Three flow patterns are characterized. Up to 100 rpm continuous radially inwards spiralling n -heptane patterns are observed. Between 100 rpm and 300 rpm this continuous spiral changes to spiralling n -heptane droplets. Above 300 rpm fully dispersed phase flow is observed. The overall Mass Transfer Rate increases from 0.17 m ORG 3 m R − 3 s − 1 at 100 rpm and a water flow Rate of 2.5 × 10 − 6 m AQ 3 s − 1 (water: n -heptane = 1.1:1) to 51.47 m ORG 3 m R − 3 s − 1 at 1600 rpm and a water flow Rate of 12.5 × 10 − 6 m AQ 3 s − 1 (water: n -heptane = 5.6:1). These Mass Transfer Rates are at least 25 times higher compared to those in packed columns, and at most 15 times higher compared to Mass Transfer Rates in state of the art microchannels.
Nulee Jang - One of the best experts on this subject based on the ideXlab platform.
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determination of volumetric gas liquid Mass Transfer coefficient of carbon monoxide in a batch cultivation system using kinetic simulations
Bioresource Technology, 2017Co-Authors: Nulee Jang, Muhammad Yasin, Robert W Lovitt, Shinyoung Park, In Seop ChangAbstract:Abstract A mathematical model of microbial kinetics was introduced to predict the overall volumetric gas–liquid Mass Transfer coefficient ( k L a ) of carbon monoxide (CO) in a batch cultivation system. The cell concentration ( X ), acetate concentration ( C ace ), headspace gas ( N co and N co 2 ), dissolved CO concentration in the fermentation medium ( C co ), and Mass Transfer Rate ( R ) were simulated using a variety of k L a values. The simulated results showed excellent agreement with the experimental data for a k L a of 13/hr. The C co values decreased with increase in cultivation times, whereas the maximum Mass Transfer Rate was achieved at the mid-log phase due to vigorous microbial CO consumption Rate higher than R . The model suggested in this study may be applied to a variety of microbial systems involving gaseous substRates.
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enhanced Mass Transfer Rate of methane via hollow fiber membrane modules for methylosinus trichosporium ob3b fermentation
Journal of Industrial and Engineering Chemistry, 2016Co-Authors: Nulee Jang, Muhammad Yasin, In Seop ChangAbstract:Abstract Polyvinylidine fluoride (PVDF) hollow fiber membranes were employed to enhance Mass Transfer Rate of methane in water for the fermentation of Methylosinus trichosporium OB3b. Compared to common alumina bubbler, hollow fiber membrane modules (HFMMs) afforded smaller methane bubble size and larger methane–water volumetric Mass Transfer coefficient (kLa) as high as 150.1 h−1. Furthermore, cell growth Rate and maximum optical density of M. trichosporium OB3b were increased by 67.3 and 77.4%, respectively, by adapting forty HFMMs, compared to those of alumina bubbler.