To sustain fluidization, or suspension of coal particles within the gasifier, coal of. Fluidization refinery application fluidization drug application fluidization at fluidization, the gravity force on the particles in the bed must be balanced fk 0 by the drag, buoyancy, and pressure forces. Fluidization powerpoint ppt presentations powershow. Poor fluidization air blowing large holes through powder surface powder level too low add powder until hopper is filled to proper level packed or moist powder a manually loosen powder and fluidize well with clean dry air b check compressed air and booth air for humidity or oil content c powder sieving may be required. This is a tool with many applications in the petroleum and chemical process industries. Fluidized bed dryer also called fluid bed dryer is a kind of equipment used extensively in the pharmaceutical industries to reduce moisture content of pharmaceutical powder and granules. However, if it is not convenient to do so, equation cd123. Fluidization free download as powerpoint presentation. Fluidization article about fluidization by the free. Fluidization occurs when small solid particles are suspended in an upwardflowing stream of fluid, as shown in figure r12. Suspensions of solid particles by vertically rising. Fluidization is necessary to explain the detailed morphology and morphometry of martian gullies e. Concepts in industrial fluidization 19 materials a are easy to fluidize. Unitoperations 1 1 introduction fluidized beds are used widely in chemical processing industries for separations, rapid mass and heat transfer operations, and catalyic reactions.
Fluidization refers to the contact between a bed of solids and a flow of fluid. University of groningen particle transport in fluidized. Either a gas or a liquid can fluidize a bed of particles. Other minimum fluidization correlations exist, but eq. Fluidized beds offer excellent heat transfer, and have the unique ability to move a wide range of solid particles in fluidlike manner.
The international fluidization conference held in henniker, new hampshire, u. In this section we describe the regions of fluidization and calculate the minimum and maximum fluidization velocities. Fluidization and its applications to food processing. P is equal to the bed weight per unit crosssectional area, and the particle sphericity. 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.
Fluidization is one of the best techniques available to disperse and process powders, but nanoparticles are very dif. The point at which this occurs depends on the particle size and density. When the gas velocities increase beyond the minimum fluidization velocity, bubbles can form. Chart and diagram slides for powerpoint beautifully designed chart and diagram s for powerpoint with visually stunning graphics and animation effects. Here, when the bed is fluidized, large pockets of gas, free of particles, are seen to rise through the bed. The majority of the solids leaving the furnace is captured by a gassolid separator, and is recirculated back to the base of the furnace. Jafari for their expert help with some aspects of this study. Smaller or lighter particles tend to experience smooth fluidization. The nps are not fluidized as individual particles, but as agglomerates.
Kunii and levenspiel 12 state that is an easily measurable value. Minimum fluidization velocity umf can be calculated theoretically using characteristic parameters like density, drag coefficient, viscosity, etc. Particulate fluidization is a condition when particles in a fluidized bed are. Mar 19, 2003 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. Fluidized beds offer excellent heat transfer, and have the unique ability to move a wide range of solid particles in a fluidlike fashion. This paper is a comprehensive revie of te siene behind fluidization of food materials, and 1ts apphcattons m. The ratio of red mud and alumina particles required to be used as the bed material was also determined by experimentation. 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. Key papers as pdf files names in blue are students who assisted with notes. Freeboard heat exchange 334 problems 334 references 335 chapter 14 the rtd and size distribution of solids in fluidized beds 337. View fluidization ppts online, safely and virusfree. Scribd is the worlds largest social reading and publishing site. A typical example is fluidized bed cracking catalyst. Worlds best powerpoint templates crystalgraphics offers more powerpoint templates than anyone else in the world, with over 4 million to choose from.
Abstract the flow of dry particulate materials is influenced by many variables, including particle shape and size distribution, density, and composition. In fluidization process, hot air is introduced at high. These gasifiers employ backmixing, and efficiently mix feed coal particles with coal particles already undergoing gasification. 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.
Mechanism of fluidised bed combustion if the sand, in a fluidized state, is heated to the ignition temperature of the fuel and the fuel is injected continuously into the bed, the fuel will burn rapidly and the bed attains a. Mathur and epstein, 1974, combustion khoshnoodi and weinberg, 1978, gasification salam and bhattacharya, 2006, waste water cleaning scott and hancher, 1976, bioreactors scott and hancher, 1976, food processing depypere et al. Applications of fluidization to food processing published online. Minimum fluidization velocity this equation can be used to calculate the minimum fluidization velocity umf if the void fraction emf at incipient fluidization is known. 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. Next, the kuniilevenspiel bubblingbed model is described in detail. Fluidization is a process in which solids are caused to behave like a fluid by blowing gas or liquid upwards through the solidfilled. Type of technology the ihi fluidized bed incinerator is a fluidized bed incinerator with a simple aeration structure and advanced combustion control technology. Fluidization new horizons in fluidization engineering engineering conferences international year 2007 presentation slides.
The application of fluidization falls into one of two general classes. Fluidization chemical engineering at the university of floridahome. Fluidization of nanoparticles was achieved as a result of the formation of stable, relatively large, and. Fluidization in tapered vessels is a useful fluidsolid contacting technique with a variety of application in drying becker and salans, 1960. Research paper waste water treatment by inverse fluidization. Basic design of a fluidized bed reactor for wastewater. Where there are particles, the bed void fraction is approximately at the value that prevails at. Fluidizedbed gasifiers suspend feedstock particles in an oxygenrich gas so the resulting bed within the gasifier acts as a fluid.
Keywords metall dynamics granular material liquid oleum. Mechanism of fluidised bed combustion if the sand, in a fluidized state, is heated to the ignition temperature of the fuel and the fuel is injected continuously into the bed, the fuel will burn rapidly and the bed attains a uniform temperature due to effective mixing. Fixed and fluidized beds university of california, berkeley. Fluidized beds offer excellent heat transfer, and have the unique ability to move a wide range of solid particles in a fluidlike. Minimum fluidization velocity an overview sciencedirect. Niranjan department of food science and technology, university of reading, food studies building, whiteknights, po box 226, reading, rg6 zap, u. Fluidization emf depends on the shape of the particles. Feb 10, 2012 fluidization can be used to process large quantities of nanopowders in the gas phase. Fluidization can be used to process large quantities of nanopowders in the gas phase. As a r esult, the solid particles are transformed into a fluidlike behavior that can be used for different. If the gasifier reactor is a circulating fluidizedbed type, the fluidization velocity in its riser figure 6. Fluid bed dryer the fluid bed dryer is used for drying granular, crystalline, coarse or similar material in pharmaceutical, fine chemicals, dyes, food and allied products.
Particulate fluidization definition and meaning collins. Theyll give your presentations a professional, memorable appearance the kind of sophisticated look that todays audiences expect. Fluidization article about fluidization by the free dictionary. Dec 23, 2015 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. The equipment works on a principle of fluidization of the feed materials. The fluidization characteristics of redmud were studied. For all practical purpose minimum fluidization velocity at which the boiler has to be operated is taken. These particles can be fluidized in a limited range of velocities in a regime similar to liquid fluidization i.
As a result, it is to some extent unpredictable and nonuniform. These are equipment in which a large surface area for contact between a liquid and a gas absorption, distillation or a solid and a gas or liquid adsorption, catalysis is obtained for achieving rapid mass and heat transfer, and particularly in. Fluidized bed reactor is widely applied in many industries for various applications recently. In contrast, bubbling fluidization occurs in gasfluidized beds. Fluidization fluidization che65 introduction to particle. This article explains the basics of fluidization theory and outlines how to design a typical fluidized bed. In practice minimum fluidization velocity is determined by a plot of superficial velocity versus pressure drop in the bed for a particular fuel. Name of technology fluidized bed incinerator ihi fluidized bed incinerator 2. Handbook of fluidization and fluidparticle systems. Hesketh1 prepared for the process fluid transport objectives 1 examine the flow regimes of a fluidized bed.
Experimentally, the most common method of measurement requires that pressure drop. Fluidizedbed combustion circulating fluidized bed boiler in a cfb boiler furnace the gas velocity is sufficiently high to blow all the solids out of the furnace. The typical fluidization velocity for silica sand of about 1 mm mean diameter may, for example, vary between 1. Winner of the standing ovation award for best powerpoint templates from presentations magazine. The authors discuss flow through fixed beds, elutriation and entrainment, gas distributor. This process occurs when a fluid liquid or gas is passed up through the granular material. This method of fluoride abatement is most effective as wastes of al industry is used to minimise another problem thereby reducing the operating cost of the al. Ppt fluidization powerpoint presentation free to download. 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. This article explains the basics of fluidization theory and. Effect of process conditions on fluidization request pdf. The fluid bed dryer is not suitable for drying liquids or pasty materials. Our new crystalgraphics chart and diagram slides for powerpoint is a collection of over impressively designed datadriven chart and editable diagram s guaranteed to impress any audience.
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