Fluidization industrial applications

Miscellaneous Systems Many other systems have been proposed for transferring heat regeneratively, including the use of high-temperature hquids and fluidized beds for direct contact with gases, but other problems which hmit industrial application are encountered. These svstems are covered by methods described in Secs. 11 and 12 of this handbook. 

Industrial Applications of Three-Phase Fluidization Systems... 

Fluidization, solids handling, and processing industrial applications / edited by Wen-Ching Yang, p. cm. 

When a chemical reaction occurs in the system, each of these types of behavior gives rise to a corresponding type of reactor. These range from a fixed-bed reactor (Chapter 21-not a moving-particle reactor), to a fluidized-bed reactor without significant carryover of solid particles, to a fast-fluidized-bed reactor with significant carryover of particles, and ultimately a pneumatic-transport or transport-riser reactor in which solid particles are completely entrained in the rising fluid. The reactors are usually operated commercially with continuous flow of both fluid and solid phases. Kunii and Levenspiel (1991, Chapter 2) illustrate many industrial applications of fluidized beds. 

Thiel WJ. The theory of fluidization and application to the industrial processing of pharmaceutical products. Int J Pharm Tech Prod Manuf 1981 2(5). Thiel WJ. Solids mixing in gas fluidized beds. Int J Pharm Tech Prod Manuf 1981 2(9). 

In the chemical engineering domain, neural nets have been applied to a variety of problems. Examples include diagnosis (66,67), process modeling (68,69), process control (70,71), and data interpretation (72,73). Industrial application areas include distillation column operation (74), fluidized-bed combustion (75), petroleum refining (76), and composites manufacture (77). 

The two-phase (gas-solid) continuous stirred-tank reactors are represented by laboratory reactors as, for instance, one-pass differential reactors, reactors with forced recirculation, one-pellet reactors, etc. The industrial applications are the fluidized beds.2 Table V presents a list of experimental studies along with a very brief description of each system studied. 

In this section we have developed steady-state and dynamic models for a hetere-geneous system. Specifically, we have chosen the bubbling fluidized bed catalytic reactor, which has many industrial applications. We have built the model for a consecutive reaction A —> B —> C with the component B being the desired component. 

The mechanical erosion of a solid surface such as a pipe wall in a gas—solid flow is characterized by the loss of solid material from the solid surface due to particle impacts. The collisions of the particles either with other particles or with a solid wall may lead to particle breakup, known as particle attrition. Pipe erosion and particle attrition are major concerns in the design of a gas-solid system and during the operation of such a system. The wear of turbine blades or pipe elbows due to the directional impact of dust or granular materials, the wear of mechanical sieves by the random impact of solids, and the wear of immersed pipes in a fluidized bed by both directional and random impacts are examples of the erosion phenomenon in industrial systems. The surface wear associated with the erosion phenomenon of a gas-solid flow has been exploited to provide beneficial industrial applications such as abrasive guns, as well. 

Standpipes are applied to fluidized bed systems in several ways. The following describes industrial applications of standpipes. An application of nonmechanical valves which control the solids flow rates is also given. 

Principles of ECT and the latest developments in the technology are highlighted with emphasis on the volume ECT (ECVT) for 3D imaging. The significance of ECT technique in process engineering is presented in the framework of industrial application. Fluidized beds, pneumatic solids conveying, and slurry bubble columns are examples of ECT s capability to provide quantitative and qualitative understanding of the internal process dynamics. 

What follows is a survey of the fluid-mechanical principles of fluidization technology, gas and solid mixing, gas-solid contact in the fluidized bed, typical industrial applications, and approaches to modeling fluidized-bed reactors. Further information is given in... 

Tawara, Y., Furuta, M., Hiura, F Ishida, Y., Uetani, J., and Harajiri, H. NSC CFB Boiler Pilot Plant Test and Industrial Application in Japan, in Circulating Fluidized Bed Technology III (Basu, P., Horio, M., and Hasatani, M., eds.), pp. 353-358. Pergamon Press, Oxford (1991). 

The Sohio process is considered one of the most successful applications of FCB. Problems in industrial application of the reaction arose from the strong exothermicity of propylene ammoxidation and from the intermediate production of acrylonitrile in the consecutive reactions (V9). It is particularly noticeable that the catalyst gives high selectivity, and the reactor design aims at better fluidization and higher contact efficiency than in the FCC process. 

Recently many inventions about fluidized catalyst beds, which are useful in industrial applications, have been reported (16-8), initiating trends... 

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