Date of Award


Document Type


Degree Name

Master of Science (MS)


Chemical Engineering


The technique of fast fluidization in gas-solid contacting was investigated. Behavior of ground sand (44-150 microns), fluid cracking catalyst (30-100 microns), and lignite (5-75 microns) in dense and fast fluidized conditions were studied.

Pressure drop measurements were made in dense fluidized beds of these particles. Incipient fluidization velocity ranged from 0.033 ft./ sec. to 0.066 ft./sec., depending on the properties of the particles. Increase in bed heights were up to 100 percent of the static bed heights.

Pressure drops and bed densities were measured for different air flows and solid flows during fast fluidization of these materials. Critical velocities of the fluidizing medium, air, which marks the lower limit of the fast fluidization range were determined to be approximately 3.5 ft./sec. for catalyst particles and about 4 ft./sec. for lignite. In the entrained state, high slip velocities were observed indicating extensive back mixing.