Fluidization is a technique that enables solid particles to take on some of the properties of a fluid. Types of fluidization obtained with different fluids kunii and levenspeil, 1962. C, a, b and d, based on their fluidization behavior. Introduction to circulating fluidized beds springerlink. Fluidization is a process in which solids are caused to behave like a fluid by blowing gas or liquid upwards through the solidfilled reactor fluidization is widely used in commercial operations. Three types of fluidization behavior have been observed which may be classified into 1 mono component. A story about liquid contra gasfluidized beds, supersonic spoutedbeds.
Lmfd latticebased multifluids dynamics is a multiphase flow simulator in framework of lattice boltzmann method lbm. Handbook of fluidization and fluidparticle systems. The point at which this occurs depends on the particle size and density. This site is like a library, use search box in the widget to get. However, similarly to other types of flow, the pressure drop across the fluidized bed. Pdf a fluidizedbed reactor was designed and constructed for practical demonstration.
Glass and steel fluidized beds are specially designed to study the effects of liquid and high temperature, two key parameters in the condensedmode operation of industrial polymerization reactors, on particle fluidization characteristics mainly from two aspects. P is equal to the bed weight per unit crosssectional area, and the particle sphericity. Particulate fluidization is a condition when particles in a fluidized bed are. Fluidization article about fluidization by the free. Pages in category fluidization the following 8 pages are in this category, out of 8 total. Fluidization and its applications to food processing. Flow through packed beds and fluidized beds citeseerx. The authors discuss flow through fixed beds, elutriation and entrainment, gas distributor. Worlds best powerpoint templates crystalgraphics offers more powerpoint templates than anyone else in the world, with over 4 million to choose from. Fluidization the processing technique employing a suspension or fluidization of small solid particles in a vertically rising stream of fluid usually gas so that fluid and solid come into intimate contact. Billy jhones a adaya ercille mae o pacamo introduction advantages and disadvantages minimum fluidizing velocity types of fluidization bed design and bubbling behavior gas flow patterns around bubble and stability davidson and harrison model discrete element analysis flow of. Reprinted with permission of the publishers the fluid velocity is sufficient to suspend the particles, but it is not large enough to carry them. Pdf the paper introduces the phenomenon of fluidization as a process. Pdf types of gas fluidization of cohesive granular materials.
Its aim is to distill from the thousands of studies those particular developments that are pertinent for the engineer concerned with predictive methods, for the. It is a program for the modeling and simulation of multiphase flows mainly gassolid twophase flows at different levels, including macroscopic twofluid model tfm. On the minimum fluidization velocity in 2d fluidized beds core. An experimental study is conducted to determine the effect of different types of nanoparticles on the gas fluidization characteristics of nanoparticle agglomerates. Analyzing the effects of particle density, size and size distribution.
Fluidization chemical engineering at the university of floridahome. A concise and clear treatment of the fundamentals of fluidization, with a view to its applications in the process and energy industries. The international fluidization conference held in henniker, new hampshire, u. In the particulate fluidization, density between and solids the fluid not too far away, with small particles and low flow rate so that the.
Production of silicon from sih4 in a fluidized bed, operation and. Unitoperations 3 2 minimum velocity of fluidization the minimum velocity at which a bed of particles. Smaller or lighter particles tend to experience smooth fluidization. Applications of fluidization to food processing sets out the established theory of fluidization and relates this to food processing applications. It presents an analysis that focuses directly on the problem of predicting the fluid dynamic behaviour of a proposed fluidized system for which empirical data is. Experimental and theoretical study of minimum fluidization. Theyll give your presentations a professional, memorable appearance the kind of sophisticated look that todays audiences expect. Abstract the flow of dry particulate materials is influenced by many variables, including particle shape and size distribution, density, and composition. The behaviour of solids fluidized by gases falls into four clearly recognizable groups, characterized by density difference. Us20070108320a1 system and method for nanoparticle and. Regular fluidization of these nanopowders can lead to two different types of fluidization. Types of gas fluidization a numerical method for distinguishing powder groups will be discussed later, in section 4. Other minimum fluidization correlations exist, but eq. This process occurs when a fluid liquid or gas is passed up through the granular material.
Experimentally, the most common method of measurement requires that pressure drop. During the analysis, the user sets the start and end drum rotation rate with the desired step rate. Fluidization can generally be made possible or improved by the use of mechanical stirrers or vibrators which break up the stable channels, or. Winner of the standing ovation award for best powerpoint templates from presentations magazine. We provide a diagram that can be used to predict these types of fluidization exhibited by cohesive powders. In fluidized bed combustion boiler technology when air or gas is passed through an inert bed of solid particles such as sand supported on a fine mesh or grid, the air initially will seek a path of least resistance and pass upward through the sand. A fixed bed b minimum or incipient fluidization, c particulate fluidization, daggregative fluidization tvoes of fluidization.
The details of the minimum velocity depend upon a number of factors, including the shape, size, density, and polydispersity of the particles. When the gas velocities increase beyond the minimum fluidization velocity, bubbles can form. Fluidized beds offer excellent heat transfer, and have the unique ability to move a wide range of solid particles in a fluidlike fashion. Download product flyer is to download pdf in new tab. Fbc fluidized bed combustion is a combustion technology used to burn solid fuels in steam boilers. Click download or read online button to get handbook of fluidization and fluid particle systems book now. Fluidization engineering, second edition, expands on its original scope to encompass these new areas and introduces reactor models specifically for these contacting regimes. Fluidization occurs when small solid particles are suspended in an upwardflowing stream of fluid, as shown in figure r12. Keywords metall dynamics granular material liquid oleum. Properties such as minimum fluidization velocity and void fraction related to limestone particles are. Fluidization or fluidisation is a process similar to liquefaction whereby a granular material is converted from a static solidlike state to a dynamic fluidlike state.
Concepts in industrial fluidization 19 materials a are easy to fluidize. Fluidized bed reactors are a kind of chemical reactors which are widely used to. In the powder processes discussed above, it is important to know the hydrodynamic behavior of the particles in fluidized beds. Completely revised and updated, it is essentially a new book. With the coupling of an external field and aeration or a flow of another gas, nanoparticles can be smoothly and vigorously fluidized.
Fluidization dynamics has been written for students and engineers who find themselves involved with problems concerning the fluidized state. Unitoperations 5 diameter d e and sphericity factor. As a result, it is to some extent unpredictable and nonuniform. Fluidization engineering kunii levenspiel pdf download. Nanoparticles nps are applied in a wide range of processes, and their use continues to increase. Geldart, 19721973 1 classified powders into four types. Normal fluidization of such powders is extremely difficult. Handbook of fluidization and fluid particle systems.
It is known that the fluidization behavior of a gassolid bed depends on the particle diameter and density. Interparticle forces exert a critical effect on particle fluidization characteristics in gassolid fluidized beds. Types of gas fluidization of cohesive granular materials. Particulate fluidization definition and meaning collins. Wikimedia commons has media related to fluidization. Fluidization technique is used for granulation as it provides good solidsolid as well as fluidsolid mixing, improves the flowability of particles, modify the bulk densities, and controlled. Minimum and full fluidization velocity for alumina used in. Revolution will begin the drum rotation at the specified start rotation rate, stepping up the rate at the desired intervals until the end rotation rate is achieved. A magnetic force andor pretreatment may be employed with the fluidizing gas and, when coupled with a fluidizing medium, provide excellent means for achieving homogenous nanofluidization.
Fluidization is one of the best techniques available to disperse and process nps. Users may download and print one copy of any publication from the public. Hesketh1 prepared for the process fluid transport objectives 1 examine the flow regimes of a fluidized bed. University of groningen particle transport in fluidized. These particles can be fluidized in a limited range of velocities in a regime similar to liquid fluidization i. This is a tool with many applications in the petroleum and chemical process industries. Apf agglomerate particulate fluidization and abf agglomerate bubbling fluidization. In broad terms, there are two main types of growth.
This article explains the basics of fluidization theory and outlines how to design a typical fluidized bed. Fluidization 2 free download as powerpoint presentation. This type of fluidization has been called aggregative. The magnetic force interacts with nonfluidizing magnetic particles and. Downloaded from the university of groningenumcg research database pure. Despite being very widely used within the food processing industry, understanding of this important technique is often limited. A typical example is fluidized bed cracking catalyst. This reference details particle characterization, dynamics, manufacturing, handling, and processing for the employment of multiphase reactors, as well as procedures in reactor scaleup and design for applications in the chemical, mineral, petroleum, power, cement and pharmaceuticals industries. The most easily recognizable features of the groups are. When a gas flow is introduced through the bottom of a bed of solid particles, it will move upwards through the bed via the empty. In this type of coal gasifier, a granular form of coal is screw fed into a fluidized bed. Fluidization types particulate fluidization aggregative fluidization particulate fluidization particulate fluidization is characterized by a large but uniform expansion of the bed at high velocities. Particle size distribution of the two types of particles used in the present study.
313 1297 1544 959 1575 749 93 1156 282 244 973 1272 1593 617 315 79 1125 940 811 1648 910 1246 42 727 810 91 20 1639 1220 833 735 797 78 1342 25 1134 422 1283 240 1436 227 1418