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Showing 1 to 18 of 18 for “"minimum fluidization velocity"”.
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Numerical Modeling and Prediction of Bubbling Fluidized Beds
… techniques are used to determine pressure drop, minimum fluidization velocity and segregation for bubbling fluidized beds. The computational fluid dynamics (CFD) code Multiphase Flow with Interphase eXchange (MFIX) is used to study a two-stage reactor geometry with a binary mixture. MFIX is …
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Utilization of cobalt catalyst for high temperature Fischer-Tropsch synthesis in a fluidized bed reactor
… The reactor was characterized to determine the minimum fluidization velocity and the maximum velocity prior to entering lean phase fluidization with pneumatic transport of the catalyst. The highest minimum fluidization velocity was found to be about 2800 sccm, there was no maximum velocity found …
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Bench-scale two-dimensional fluidized bed hydrodynamics and struvite growth studies
… designed and studies of hydrodynamic behavior of fluidization of struvite pellets were performed. Also size growth distribution tests were analyzed qualitatively. The study validated a previously-proposed theory, concerning the relationship between dynamic pressure drop and upflow velocity as well …
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Improvement of Fluidization Ability for Group A Powders by Fine Powder Additives
… in the industry because of the great quality of fluidization, which can be affected by the fine content. This project investigates the feasibility that employing the fine powders (≤ 20 μm) as additives to further improve the fluidization ability of Group A powders. Three additives, Coal-15, GB-6, …
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Visualizing fluidized beds with X-rays
<p>This study applies minimum fluidization velocity experiments, X-ray computed tomography (CT), X-ray stereography, and particle tracking to fluidized beds of glass beads, ground walnut shell, and ground corncob operating with a variety of flow conditions. 3-D local, time-averaged gas holdup is …
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Jet assisted fluidization of nanoparticle agglomerates
Fluidization serves as a primary operation used to disperse, handle and process nanoparticles, but due to the complications involved with achieving homogenous fluidization of the agglomerates of nanoparticles, several methods have been developed to assist their conventional mode of fluidization. In …
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CPFD Modeling of a Novel Internally Circulating Bubbling Fluidized Bed for Chemical Looping Combustion
… work was first conducted investigating the minimum fluidization velocity (Umf), gas bubble size, and tube-to-bed heat transfer coefficients of different ilmenite particle size distributions (PSDs) at varying pressures up to 2000 kPa. The data was compared to a variety of literature …
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Inverse solid-liquid fluidization of aerogel granules and its application in removing oil from water
Fluidization is a very well known unit operation used in the chemical industry for various purposes. Inverse solid-liquid fluidization, where the solid particles to be fluidized are less dense than the fluid, is one of the several different kinds of fluidization being studied for its potential in …
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Mass transfer in aerated vibrated beds
… bed if the gas stream is greater than the minimum fluidization velocity of the particles. Mass transfer rates from solid particles coated with naphthalene to a nitrogen stream, the fluidizing gas, are determined using a gas chromatographic technique. Two kinds of coated beads of different …
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Pyrolysis and Hydrodynamics of Fluidized Bed Media
… gasifier designs. This research investigates bed fluidization and particle decomposition for fluidized materials. Experimental methods were developed to model gravimetric and energetic response of thermally decomposing materials. Gravimetric, heat flow, and specific heat data were obtained from a …
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Fluidization and soot filtration in a rotating fluidized bed
… necessitating an understanding of the nature of fluidization, particle mixing and filtration in the RFB. In an RFB, particles are subject to a centrifugal force which can be much larger than the force of gravity. Therefore the Geldart classification for conventional fluidized beds must be …
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A Computational Study of the Hydrodynamics of Gas-Solid Fluidized Beds
… granular kinetic theory were used to simulate fluidization and to capture the complex physics associated therewith. The commercial code ANSYS FLUENT was used to study two-dimensional single solids phase glass bead and walnut shell fluidized beds. Current modeling codes only allow for modeling …
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Eulerian-Eulerian Modeling of Fluidized Beds
… mass model was shown to accurately predict fluidization characteristics such as pressure drop and minimum fluidization velocity. The effectiveness of the adjusted mass model was further illustrated by applying it to fluidized beds containing coal, switchgrass, poplar wood, and cornstover …
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PERFORMANCE ANALYSIS AND THE EFFECTS OF KEY PARAMETERS IN SOLID PARTICLE BEDS
… of the existing numerical models for determining minimum fluidization velocity (u_mf), the effects of the key parameters in bed optimization, the turbulence-like behavior initiating from three-dimensionality, quantification of bed performance, and jet-like patterns in uniform inflow. The Eulerian …
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The behaviour of freely bubbling fluidized beds
… the academic and industrial engineer. Although fluidization phenomena have been the subject of many hundreds of papers we still cannot dispense with experimentation in order to predict bed behaviour even for relatively simple operations, let alone complex chemical reactions. This thesis provides …
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Gas fluidization of nanoparticles
… to perform a systematic investigation on the gas fluidization of various nanoparticle agglomerates. Firstly, the gas fluidization characteristics and regime classifications without any additional external force fields are identified using both experimental measurements and modeling. Secondly, the …
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Mixing of nanosize particles by magnetically assisted impaction techniques
… down the larger agglomerates, to reduce the minimum fluidization velocity, to delay the onset of bubbling, and to convert the fluidization behavior of ABF powder to APF. Thus MAIM techniques may be used to achieve mixing of nanopowders at a desired HoM through adjusting the number of magnets …
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Air slide basic modelling
… developed which could be used to predict the velocity and mass flow rates of alumina flow and capacity of an air slide for a range of alumina qualities. Such a model would be extremely useful when designing new air slide systems, as the capacity of air slides could be predicted from the …