Chemical engineering science fluidized bed applications. Operation procedures of this process include adding pellets into a column reactor and directing raw water and chemicals through the bottom of the column, keeping pellets fluidized to prevent them from being coagulated. Moving particles, especially small particles, can transport heat much more efficiently than gas alone. Fundamentals of fluidizedbed chemical processes 1st edition. Fcc process is very complex and require good understanding of many factors such as kinetic models, reaction kinetic, fluid dynamics, feed and catalyst effects, temperature, residence time in the riser, catalyst deactivation and its regeneration. Simulation of circulating fluidized bed reactors using aspen plus. May 23, 2012 modeling and measurement of bubble size in a rotating fluidized bed 1 january 2007 aiche journal, vol. Extensive studies are available on fluidized bed reactor hydrodynamics and reaction engineering models. Basic design of a fluidized bed reactor for wastewater. These pages were constructed to convey the importance of fluidized bed reactors fbrs in todays petroleum and chemical process industries. Pla doesnt need an input gas from my understanding. A particular focus is to describe the relationship between catalyst attrition, solids recovery in the reactor system, and chemical performance of the fluidized bed reactor. Fluidization occurs when small solid particles are suspended in an upwardflowing stream of fluid, as shown in figure r12.
Bed agglomeration during biooil fast pyrolysis in a fluidized bed reactor. A modeling approach is presented that is able to handle the most important aspects of industrial fluidized bed reactors. The heat capacity of the solids in a fluidized bed allows the solid particles themselves to be used as a heat. Fluidized bed reactors are commonly used in catalytic cracking processes. The canadian journal of chemical engineering, 73, pp. Flow through a bed of particles response to superficial flow fluid does not impart enough drag to overcome gravity and particles do not move. Abstractfluidized bed reactor fbr can be an efficient alternative.
Thus, the benefits of using fluidized bed technology can easily outweigh the disadvantages, especially for processes. Fluidized bed reactor an overview sciencedirect topics. Their applications in fluidized bed reactors are limited. The distinguishing feature of a fluidized bed reactor is that the bed of solid particles or catalyst is supported by an up flow of gas. Development of a continuous fluidized bed reactor for. Earlier, davidsons approach of modeling a bubbling fluidized bed reactor was the key contribution in accounting for bubble scale related transport phenomena. Indirect heat transfer to fluidized bed reactors using coils or stabin heat exchange bundles is therefore often effective. The reactor is designed to operate with a nio oxygen carrier and is fueled with either natural gas or designed mixtures of ch 4, co, h 2, and higher hydrocarbons at 120. Even for the most extreme exothermic reactions, a fluidized bed can maintain an isothermal profile within a few degrees. The heattransfer rate in a fluidized bed can be five to ten times greater than that in a packed bed reactor.
Bottom port for input gas and a gas distributor plate to make it a fluidized bed reactor, side ports to inject additional reactantscatalysts or remove product. Optimum mixing in the bed is achieved within specific velocity limits that are function of the particle size of bed material 22. Consequently, a detailed design of a fluidized bed reactor that would allow flexible operation at high temperature and high pressure at several gas velocities will be conducted in order to serve for the future development of new hydrodynamic models. Likewise, the successful application of fluidized bed reactors to highly exothermic oxidation processes, such as those cited above for the chemical process industries, is due to the ability of the reactor to control the exothermic reactions which are taking place. Nov 24, 2015 fluidized bed, used for fluidization a fluidized bed is formed when a quantity of a solid particulate substance usually present in a holding vessel is placed under appropriate conditions to cause a solidfluid mixture to behave as a fluid. This paper compares data obtained in an industrial phthalic anhydride reactor of 2. The fluidized bed reactor page university of washington. This work is focused on applicability of the fluidizedbed reactor fbr concept for ocm and testing the novel idea of fluidizedbed membrane reactor fbmr for the first. Basic design of a fluidized bed reactor for wastewater treatment. Numerical simulation of biomass fast pyrolysis in fluidized bed and auger reactors soroush aramideh iowa state university follow this and additional works at. A good model for the reactor fluid dynamics is essential to properly set the operating. This is to certify that the thesis entitled fluidized bed reactor.
This reactor possesses an overall volume of 100 l with the expanded bed volume taking up 30 l. The performance of the ceb reactor was investigated in a o. Compounds in petroleum coke fluidized bed combustion fbc ash. A fluidized bed reactor was designed and constructed for practical demonstration of the fluidization of solid particles at different fluid flow rates. In recent years, the circulating fluidized bed as a reactor has experienced increasing application in industry. A fluidized bed reactor fbr is a combination of the two most common configurations, stirred tank and packed bed continuous flow reactors.
My thinking was to use the same body for all of the reactors, though with progressively more ports for additional capabilities. The formulas for the design parameters are to be selected from vast literature available on researches in fluidized bed reactors and the study of fluidization profiles. Phenol degradation in an anaerobic fluidized bed reactor packed with low density support materials 89 brazilian journal of chemical engineering vol. Parr fluidized bed reactors are used extensively in the chemical process industries. A fluidized bed membrane bioelectrochemical reactor for energyefficient wastewater treatment. Fundamentals of fluidized bed chemical processes presents a survey of the design, operation, and chemical processes of fluidized bed reactors. Iran mirzaei, ahmad iran polymer and petrochemical institute, faculty of polymerization engineering, tehran, i.
In fbr, cells are attached to solids in the form of biofilm or granules. The heat of reaction of the exothermal hydration reaction is removed by water, evaporating in a cooling coil, immersed in the fluidized bed. International journal of engineering and computer science. It has excellent heat and masstransfer characteristics. Experimental and numerical study of wall layer development in. Pdf basic design of a fluidized bed reactor for wastewater. Scribd is the worlds largest social reading and publishing site. Fluidized bed reactors offer a much higher efficiency in heat exchange, compared to fixed beds, and better temperature control, due to the turbulent gas flow and rapid circulation.
Removal of fluoride by crystallization process in a fluidized bed reactor using granular calcite as seed material has been carried out in a laboratoryscale fluidized bed reactor in order to study. Analysis of fluidizedbed and fluidizedbedmembrane reactor. The effects of triboelectricity in a smallscale fluidized bed of polyethylene particles were investigated by imaging the particle layer in the vicinity of the column wall and by measuring the pressure drop across the bed. As a first operating result, a pressure profile in hot. Feasibility of rotating fluidized bed reactor for rocket. Riser system with ozone decomposition in the reactor. Methods and apparatus for the production of high purity silicon including a fluidized bed reactor with one or more protective layers deposited on an inside surface of the fluidized bed reactor.
Fixed and fluidized beds university of california, berkeley. Apply basic equations to compute pressure drop across the bed, the bed height and the diameter of the bed. Softening by fluidized bed crystallizers article pdf available in journal of environmental engineering 1184 july 1992 with 287 reads how we measure reads. Nitrate is present in the majority of water resources, and has reached serious level in many parts of the world, which is responsible for environmental problems. Semantic scholar extracted view of basic design of a fluidized bed reactor for wastewater. The different sections of this archive are accessed through the links below. International journal of innovation, management and technology, vol.
Control of a fluidized bed polyethylene reactor vahidi, omid. Burwell sm, najman j, bulewicz em 2006 understanding the behavior of calsium compounds in petroleum coke fluidized bed combustion fbc ash. Integrated particle and reactor scale simulation of pine pyrolysis in a fluidized bed. Fluidized catalytic cracking riser reactor operating process. Fluidized bed reactors have been studied in several reactor engineering researches for ocm, also quite stable and efficient performance was reported. Fluidized bed reactors are theoretically an excellent reactor type choice for highly exothermic reactions, such as the ft reaction. Us8168123b2 fluidized bed reactor for production of high. List advantages and disadvantages of fluidized beds. Two radiation furnaces 64 kw are used to heat the reactor. The first chapter examines the basic physics of gassolid fluidization. Although accumulation of material inside the reactor was a main problem, this was avoided by removing and adding bed media along gasification. This is usually achieved by the introduction of pressurized fluid through the particulate medium. Generalized bubblingslugging fluidized bed reactor model. Modeling of industrial fluidizedbed reactors industrial.
Pdf performance of fluidized bed biofilm reactor for. A circulating fluidized bed cfb has some unique features as a chemical reactor. Pdf fluidization characteristics of a prototype fluidized bed. The protective layer may be resistant to corrosion by fluidizing gases and siliconbearing gases. Pdf simulation of circulating fluidized bed reactors. Pdf a fluidizedbed reactor was designed and constructed for practical. They are also used in the oxidation of naphthalene to phtalic anhydride, roasting of sulfide ores, coking of petroleum residues, and the calcination of limestone. Table i represents the variety of studies done on some pollutant degradation on fluidized bed reactor. An experimental investigation of sewage sludge gasification. The average charge on the particles was altered by changing the relative humidity of the gas. Prototypefluidized bed reactor, dehydrogenation, minimum fluidising. Fluidized beds have high heat transfer coefficients. In addition, reactors can be coupled such that the catalyst can be cycled and regenerated. A dual circulating fluidized bed dcfb reactor system for chemical looping combustion is proposed.
166 81 384 1638 827 1407 225 774 618 77 1426 887 211 20 1195 1470 8 953 384 664 1251 43 467 1345 728 1047 275 1349 1146 505 1076 1383 1233 206 815