Fate of solids fed pneumatically through a jet into a fluidized bed

Journal Article · Sun Jan 01 04:00:00 EST 1984 · AIChE J.; (United States)

DOI:https://doi.org/10.1002/aic.690300115· OSTI ID:6686051

Kececioglu, I; Keairns, D L; Yang, W C

Solid tracer particles were fed pneumatically through a jet into a fluidized bed to simulate the feeding of solids via a pneumatic transport line into a fluidized-bed reactor operating in the slugging-bed mode. The fluidized bed was defluidized instantaneously at different times after the initiation of the tracer particle injection. The bed was then sampled layer by layer to provide the radial and axial concentration profiles of the tracer. Regular and high-speed movies (1,000 frames per second) were taken to study the operation of the fluidized bed and the phenomena of the gas-solid two-phase jet. Experimental results on solid mixing, jet constriction and slugging frequencies, slugging bed height, slug length, jet penetration, and jet half-angle at three nominal jet velocities of 52, 37, and 25 m/s and corresponding solids loadings are presented. Additional experimental results on jet constriction and slugging frequencies, and slug volume (axial slug size) obtained for a wider range of jet velocities confirm the hydrodynamic trends observed during the tracer particle injection experiments. The results indicate that solids mixing increases, and well-mixed conditions are reached earlier, with an increase in jet injection velocity. The obtained mixing times were correlated successfully in terms of the excess gas velocity. The experimental data on jet penetration and slug motion were satisfactorily correlated by modified versions of existing theoretical relations. The modifications included the effect of the injected solids on jet penetration and jet half-angle and also the effect of our semicircular column geometry and single wall-slug configuration on the observed slug motion.

• Research Organization: Westinghouse Research and Development Center, Pittsburgh, PA 15235
• DOE Contract Number: AC01-76ET10161
• OSTI ID: 6686051
• Journal Information: AIChE J.; (United States), Journal Name: AIChE J.; (United States); ISSN AICEA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
CHEMICAL REACTORS
DATA
DIMENSIONS
EXPERIMENTAL DATA
FLUID MECHANICS
FLUIDIZED BED
FLUIDS
GASES
GEOMETRY
HEIGHT
HYDRODYNAMICS
INCIDENCE ANGLE
INFORMATION
JETS
LAYERS
LENGTH
MATHEMATICS
MECHANICS
MIXING
NUMERICAL DATA
PARTICLES
PNEUMATIC TRANSPORT
SAMPLING
SOLIDS
TRANSPORT
VELOCITY
VOLUME