Heat transfer to a liquid fluidized bed

✍ Scribed by Robert Lemlich; Isidoro Caldas Jr.

• Publisher: American Institute of Chemical Engineers
• Year: 1958
• Tongue: English
• Weight: 537 KB
• Volume: 4
• Category: Article
• ISSN: 0001-1541
• DOI: 10.1002/aic.690040328

✦ Synopsis

An experimental study of the rate of heat transfer from the retaining wall to a fluidized bed of solids was carried out for liquid water and glass spheres. The independent variables included mass velocity, particle size, bulk temperature, and wall temperature. Significant increases in heat transfer were observed, owing to the presence of the suspended solids, even to the extent of tripling the coefficient. For each of several particle sizes, the coefficient passed through a maximum corresponding to a particular mass velocity. The behavior of the bed at velocities below and above those for maximum coefficient was studied and categorized. Tentative correlations for both regions are offered.

N u c h work in recent years has dealt with heat transfer in fluidized beds. However, published data dealing with heat transfer from the retaining wall t o the bed appear t o be limited to systems wherein the fluid itself is a gas. Virtually nothing could be found for t h e case of a liquid. Accordingly, the present investigation was undertaken in an effort t o study the transfer of heat from a vertical cylindrical retaining tube t o a fluidized bed consisting of solid spheres suspended in water. The independent ,variables included mass velocity, particle diameter, wall temperature, and, to a lesser extent, bulk temperature and bed height.

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