Fluidized beds method

Alternatives to the fluidized-bed method process include the chlorination of titanium slags in chloride melts, chlorination with hydrogen chloride, and flash chlorination. The last is claimed to be particularly advantageous for minerals having a high impurity content (133—135,140). The option of chlorinating titanium carbide has also been considered (30). 

Two other techniques use attached microorganisms for remediation. In a fluidized-bed method, the microorganisms are attached to particles dispersed throughout a continuously stirred reactor. In another arrangement, the microorganisms are attached to rotating discs. 

KullendrofT, A., Herstad, S., and Olofason, J. Control of NO and SO Emissions by Combustion in Circulating Fluidized Beds—Methods and Operating Experiences, VGB Conf Power Station Environment 1985, Essen, West Germany KullendrofT, A. (1985). 

Manufacture. Due to its low melting viscosity, PBCMO can be easily produced by conventional injection molded procedures. Coatings can be applied by the usual techniques as a solution, dispersion, or dry powder. Heavy coatings to complex metal objects are applied by the fluidized bed method. 

Figure 6.60. Illustration of two methods used for the commercial production of SWNTs. Shown are (a) the CoMoCat fluidized bed method using CO as the precursor and a Co/Mo bimetallic catalyst,[84] and (b) the HiPco floating catalyst process using the thermal decomposition of iron pentacarbonyl at pressures of 1-10 atm.[85]...

Yueksel N. Karatas A. Baykara T. Comparative evaluation of granules made with different binders by a fluidized bed method. Drug Dev Ind Pharm 2003 29(4) 3 7-95. 

The fluidized-bed method worked well, and it thoroughly deagglomerates dry and relatively noncohesive powders, such as coal, Arizona road dust, silica, copper ore, and potash [63]. The fluidizing action of the bed alone was inadequate for deagglomerating flocks of fibers and cohesive powders, such as dyes, that consist of relatively flat particles [69]. Air-impaction methods worked better. 

Flow methods, because they readily remove desorbed species, are one of the best methods for studying desorption kinetics. Sparks et al. (1980) used the miscible displacement method to study K desorption kinetics. However, mass transfer processes are clearly rate limiting with this method, and thus great care must be used in interpreting the results. The previous discussion on the limitations of this method is relevant to desorption studies. Stirred-flow or fluidized bed methods can be used to minimize diffusion in desorption experiments, but they have not yet been used specifically for desorption studies. 

On the formation of the Department of Chemical Engineering in 1920 he served as its first head until 1929, when he returned to teaching and research. Just prior to World War II, Dr. Lewis and Dr. Gilliland invented the fluidized-bed method of cracking for petroleum which made possible the enormous production of aviation gasoline so vital in that confiict. Dr. Lewis was Vice Chairman of the Chemistry Division of the National Defense Research Committee, served in the OflBces of Scientific and Production R D and on chemical engineering problems in the development of the atomic bomb. 

Fluidized-Bed Method. The fluidized bed consists of inert, finely granular, inorganic material (usually alumina) that is fluidized by injecting compressed air through... 

SWNTs have been successfully synthesized using a fluidized-bed method [60] that involves fluidization of a catalyst/support at high temperatures by a hydroearbon flow. 

Ecord [37]. The base metal is packed into a powdered mixture composed of the metal to be diffused, an inert filler, and an activator (usually a halide salt). The use of an activator allows that the temperature to be used is lower than that which would be required by a conventional cementation process. The sealed pack is then held at a given temperature in a furnace for an appropriate time. Parts to be coated by the fluidized bed method are suspended in a bed of the coating metal, which is fluidized by a halogen gas stream mixed with an inert carrier gas. This is similar to the flowing gaseous methods in which the gaseous metal halide (of the coating metal) is streamed over the metal to be coated. 

It is possible to determine overall crystal growth rates by adding a known mass of sized seeds to a supersaturated solution in an agitated vessel, following a similar procedure to that outlined above for the fluidized bed method. To correlate the data, however, it is necessary to estimate the particle-fluid slip velocity as a function of impeller speed in the agitated vessel using relationships of the type described in section 9.4.1. 

The Fischer-Tropsch synthesis leads almost exclusively to aliphatic hydrocarbons and oxygen compounds the proportion of aromatics depends on the type of reactor system used. The aromatics content of the gasoline and diesel oil produced by the fixed-bed process in the SASOL I plant is negligible, while the aromatics content of gasoUne produced by the fluidized-bed method by SASOL II and III is around 7%, and the level in diesel oil 10%. The increase in aromatics with the fluidized-bed reactor is a result of the reaction temperature, which is approximately 100 °C higher. Since the concentration is rather low, it is not economical to... 

Coatings of polyethylene powder are applied by the fluidized-bed method, the flame spraying method, or the dispersion method. Tests of coatings depend on the shape, dimension, and final application of the coated metals. 

A fluidized bed method is used to apply relatively thick thermoplastic powder coatings. The article to be coated is heated above the Tg of the binder resin and then suspended in a fluidized bed of coating powder. Powder particles fuse onto the object imtil the powder layer becomes sufficiently thick to act as a thermal insulator and prevent additional fusing. Since the surface may contain incompletely fused particles, the operation is completed in a separate oven. Electrostatic fluidized beds are also used, with charged powder and grounded substrates, which may or may not be preheated. 

The fluidized-bed method can be used when the polymer is a reactive powder. A mixture of an epoxy resin and an acid hardener can be fluidized and deposited simultaneously. Reaction occurs only on the hot surface. 

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