Engineering of fluidized bed

Basic two-phase model of fluidized bed. Open arrows indicate movement of solids. (Adapted from Fluidization Engineering by D. Kunii and O. Levenspiel. Copyright 1969. Reprinted by permission of John Wiley and Sons, Inc.)... 

The early 1970 s saw the development of many new coal-based, synthetic-fuel, fluidized-bed processes which operated at high pressures. The scientists and engineers charged with designing these processes realized that there was a severe lack of information on how pressure (and also temperature) affected the operation of fluidized beds. Therefore, several studies to determine the effect of pressure on the operation of fluidized beds were commissioned. During the same period, other researchers in Japan, Europe, and the U.S. were also starting to conduct research to determine the effects that temperature and pressure have on fluidized systems. 

One of the strengths of the KTGF, although still under development, is that it can offer a very clear physical picture with respect to the key parameters (e.g., particle pressure, particle viscosity, and other transport coefficients) that are used in the TFMs. The TFMs based on KTGF requires less ad hoc adjustments compared to the other two types of models. Therefore, it is the most promising framework for modeling engineering-scale fluidized beds. 

The effects of adsorption and desorption on the performance of fluidized beds are discussed elsewhere. Adsorption of carbon disulfide vapors from air streams as great as 300 nr/s (540,000 ft3/min) in a 17-m- (53-ft-) diameter unit has been reported by Avery and Tracey ( The Application of Fluidized Beds of Activated Carbon to Recover Solvent from Air or Gas Streams, Tripartate Chemical Engineering Conference, Montreal, Sept. 24, 1968). 

Figure 3.2 Variation of fluidized bed freezer capacity with bed depth (solid line = freezing capacity, broken line = mass per unit power consumption). Adapted from Persson, ASHRAE Journal, June 1967. American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc., www.ashrae.org.

Avery, D. A. Tracey, D. H. "The Application of Fluidized Beds of Activated Carbon to Solvent Recovery from Air or Gas Streams," Institution of Chemical Engineers Symposium Series, No. 30, 1968. 

Since its foundation the Department of Chemical Engineering and Industrial Chemistry of the V.U.B. acquired considerable experi-eice in the field of high temperature processes, -with studies on steam-reforming of natural gas, pyrolysis of hydrocarbons and catalytic combustion of hydrocarbons. The Department conducted fundamental studies as well as contract work for industry, e.g. in the domain of fluidized bed techniques, incinerator grate mechanisms and small waste-fed boilers. An assessment on current thermal disposal techniques was prepared on behalf of E.E.C.[ 5 57958] ... 

Bolthrunis, C.O. Silverman, R.W. Ferrari, D.C. Rocky road to commercialization breakthroughs and challenges in the commercialization of fluidized bed reactors. In Fluidization XI Present and Future for Fluidization Engineering Arena, U., Chirone, R., Miccio, M., Salatino, P., Eds. Engineering Foundation New York, 2004 547-554. 

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