The Experts below are selected from a list of 321 Experts worldwide ranked by ideXlab platform
William B Zimmerman - One of the best experts on this subject based on the ideXlab platform.
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Aerator design for microbubble generation
Chemical Engineering Research & Design, 2017Co-Authors: James Hanotu, Hemaka C H Bandulasena, William B ZimmermanAbstract:Abstract Fine bubbles are a key component in improving the performance of gas-liquid reactors, particularly in situations where reactions are mass transfer limited. Many Aerator types exist for different reactor applications; however conventional Aerators are mostly suited to coarse bubble generation. A new Aerator suitable for microbubble generation by fluidic oscillation has been designed and tested with the view of getting a uniform bubble distribution across the Aerator. Microbubbles generated from various membrane pore sizes and oscillation frequencies were characterized for this Aerator to determine the optimum operating parameters. It was evident that the introduction of a flow distributor plate to the plenum chamber improved gas distribution from the inlet to the porous membrane leading to uniform bubble generation across the entire Aerator. The resultant average bubble size from this new design under oscillatory flow was found to be approximately 2–3 times the membrane pore size. This outcome has a great potential to promote the efficiency of multiphase reactors where mass transfer plays a key role.
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Aerator Design for Microbubble Generation
Chemical Engineering Research and Design, 2017Co-Authors: James Hanotu, Hemaka C H Bandulasena, William B ZimmermanAbstract:This paper is in closed access until 16th Mar 2018.Fine bubbles are a key component in improving the performance of gas-liquid reactors,\ud particularly in situations where reactions are mass transfer limited. Many Aerator types\ud exist for different reactor applications; however conventional Aerators are mostly suited to coarse bubble generation. A new Aerator suitable for microbubble generation by fluidic oscillation has been designed and tested with the view of getting a uniform\ud bubble distribution across the Aerator. Microbubbles generated from various membrane\ud pore sizes and oscillation frequencies were characterized for this Aerator to determine\ud the optimum operating parameters. It was evident that the introduction of a flow\ud distributor plate to the plenum chamber improved gas distribution from the inlet to the porous membrane leading to uniform bubble generation across the entire Aerator The\ud resultant average bubble size from this new design under oscillatory flow was found to\ud be approximately 2-3 times the membrane pore size. This outcome has a great potential\ud to promote the efficiency of multiphase reactors where mass transfer plays a key role
James Hanotu - One of the best experts on this subject based on the ideXlab platform.
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Aerator design for microbubble generation
Chemical Engineering Research & Design, 2017Co-Authors: James Hanotu, Hemaka C H Bandulasena, William B ZimmermanAbstract:Abstract Fine bubbles are a key component in improving the performance of gas-liquid reactors, particularly in situations where reactions are mass transfer limited. Many Aerator types exist for different reactor applications; however conventional Aerators are mostly suited to coarse bubble generation. A new Aerator suitable for microbubble generation by fluidic oscillation has been designed and tested with the view of getting a uniform bubble distribution across the Aerator. Microbubbles generated from various membrane pore sizes and oscillation frequencies were characterized for this Aerator to determine the optimum operating parameters. It was evident that the introduction of a flow distributor plate to the plenum chamber improved gas distribution from the inlet to the porous membrane leading to uniform bubble generation across the entire Aerator. The resultant average bubble size from this new design under oscillatory flow was found to be approximately 2–3 times the membrane pore size. This outcome has a great potential to promote the efficiency of multiphase reactors where mass transfer plays a key role.
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Aerator Design for Microbubble Generation
Chemical Engineering Research and Design, 2017Co-Authors: James Hanotu, Hemaka C H Bandulasena, William B ZimmermanAbstract:This paper is in closed access until 16th Mar 2018.Fine bubbles are a key component in improving the performance of gas-liquid reactors,\ud particularly in situations where reactions are mass transfer limited. Many Aerator types\ud exist for different reactor applications; however conventional Aerators are mostly suited to coarse bubble generation. A new Aerator suitable for microbubble generation by fluidic oscillation has been designed and tested with the view of getting a uniform\ud bubble distribution across the Aerator. Microbubbles generated from various membrane\ud pore sizes and oscillation frequencies were characterized for this Aerator to determine\ud the optimum operating parameters. It was evident that the introduction of a flow\ud distributor plate to the plenum chamber improved gas distribution from the inlet to the porous membrane leading to uniform bubble generation across the entire Aerator The\ud resultant average bubble size from this new design under oscillatory flow was found to\ud be approximately 2-3 times the membrane pore size. This outcome has a great potential\ud to promote the efficiency of multiphase reactors where mass transfer plays a key role
Kefa Cen - One of the best experts on this subject based on the ideXlab platform.
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Improving microalgal growth with small bubbles in a raceway pond with swing gas Aerators
Bioresource technology, 2016Co-Authors: Zongbo Yang, Jun Cheng, Junhu Zhou, Jianzhong Liu, Kefa CenAbstract:A novel swing gas Aerator was developed to generate small bubbles for improving the mass transfer coefficient and microalgal growth rate in a raceway pond. A high-speed photography system (HSP) was used to measure the bubble diameter and generation time, and online precise dissolved oxygen probes and pH probes were used to measure the mass transfer coefficient and mixing time. Bubble generation time and diameter decreased by 21% and 9%, respectively, when rubber gas Aerators were swung in the microalgae solution. When water pump power and gas aeration rate increased in a raceway pond with swing gas Aerators and oscillating baffles (SGAOB), bubble generation time and diameter decreased but solution velocity and mass transfer coefficient increased. The mass transfer coefficient increased by 25% and the solution velocity increased by 11% when SGAOB was used, and the microalgal biomass yield increased by 18%.
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Improving microalgal growth with reduced diameters of aeration bubbles and enhanced mass transfer of solution in an oscillating flow field
Bioresource technology, 2016Co-Authors: Zongbo Yang, Jun Cheng, Richen Lin, Junhu Zhou, Kefa CenAbstract:A novel oscillating gas Aerator combined with an oscillating baffle was proposed to generate smaller aeration bubbles and enhance solution mass transfer, which can improve microalgal growth in a raceway pond. A high-speed photography system (HSP) was used to measure bubble diameter and generation time, and online precise dissolved oxygen probes and pH probes were used to measure mass-transfer coefficient and mixing time. Bubble diameter and generation time decreased with decreased aeration gas rate, decreased orifice diameter, and increased water velocity in the oscillating gas Aerator. The optimized oscillating gas Aerator decreased bubble diameter and generation time by 25% and 58%, respectively, compared with a horizontal tubular gas Aerator. Using an oscillating gas Aerator and an oscillating baffle in a raceway pond increased the solution mass-transfer coefficient by 15% and decreased mixing time by 32%; consequently, microalgal biomass yield increased by 19%.
Hemaka C H Bandulasena - One of the best experts on this subject based on the ideXlab platform.
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Aerator design for microbubble generation
Chemical Engineering Research & Design, 2017Co-Authors: James Hanotu, Hemaka C H Bandulasena, William B ZimmermanAbstract:Abstract Fine bubbles are a key component in improving the performance of gas-liquid reactors, particularly in situations where reactions are mass transfer limited. Many Aerator types exist for different reactor applications; however conventional Aerators are mostly suited to coarse bubble generation. A new Aerator suitable for microbubble generation by fluidic oscillation has been designed and tested with the view of getting a uniform bubble distribution across the Aerator. Microbubbles generated from various membrane pore sizes and oscillation frequencies were characterized for this Aerator to determine the optimum operating parameters. It was evident that the introduction of a flow distributor plate to the plenum chamber improved gas distribution from the inlet to the porous membrane leading to uniform bubble generation across the entire Aerator. The resultant average bubble size from this new design under oscillatory flow was found to be approximately 2–3 times the membrane pore size. This outcome has a great potential to promote the efficiency of multiphase reactors where mass transfer plays a key role.
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Aerator Design for Microbubble Generation
Chemical Engineering Research and Design, 2017Co-Authors: James Hanotu, Hemaka C H Bandulasena, William B ZimmermanAbstract:This paper is in closed access until 16th Mar 2018.Fine bubbles are a key component in improving the performance of gas-liquid reactors,\ud particularly in situations where reactions are mass transfer limited. Many Aerator types\ud exist for different reactor applications; however conventional Aerators are mostly suited to coarse bubble generation. A new Aerator suitable for microbubble generation by fluidic oscillation has been designed and tested with the view of getting a uniform\ud bubble distribution across the Aerator. Microbubbles generated from various membrane\ud pore sizes and oscillation frequencies were characterized for this Aerator to determine\ud the optimum operating parameters. It was evident that the introduction of a flow\ud distributor plate to the plenum chamber improved gas distribution from the inlet to the porous membrane leading to uniform bubble generation across the entire Aerator The\ud resultant average bubble size from this new design under oscillatory flow was found to\ud be approximately 2-3 times the membrane pore size. This outcome has a great potential\ud to promote the efficiency of multiphase reactors where mass transfer plays a key role
John C Little - One of the best experts on this subject based on the ideXlab platform.
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predicting oxygen transfer and water flow rate in airlift Aerators
Water Research, 2002Co-Authors: Vickie L Burris, Daniel Frank Mcginnis, John C LittleAbstract:Water flow rate, gas-phase holdup, and dissolved oxygen (DO) profiles are measured in a full-scale airlift Aerator as a function of applied air flow rate. A model that predicts oxygen transfer based on discrete-bubble principles is applied. The riser DO profiles are used to calculate the initial bubble size. The range of calculated bubble diameters obtained using the model is 2.3–3.1 mm. The Sauter-mean diameter of bubbles measured in the laboratory ranged from 2.7 to 3.9 mm. The riser and downcomer DO profiles and gas holdups predicted by the model are in close agreement with the experimental results. A model that predicts water flow rate based on an energy balance is used to calculate Kt, the frictional loss coefficient for the air–water separator. Excluding the data at the very lowest air flow rate, the range of calculated values for Kt (3–8) is close to a literature value of 5.5 proposed for hydrodynamically similar external airlift bioreactors. The models should prove useful in the design and optimization of airlift Aerators.