Record Details
Field | Value |
---|---|
Title | Effectiveness of a fluidized bed in filtration of airborne particulate of submicron size |
Names |
Black, Charles Hartgraves
(creator) Boubel, Richard W. (advisor) |
Date Issued | 1966-10-07 (iso8601) |
Note | Graduation date: 1967 |
Abstract | Submicron particulate (mean size of 0.52 microns) was filtered from air at substantially atmospheric temperature and pressure by passing air up through a bed of fluidized glass shot in a two inch column. Removal efficiency, defined as the percentage removal of particulate from the air stream, was essentially constant during the life of the bed and independent of the entering concentration over the range of 0.1 to 5 milligrams per cubic meter. Varying superficial gas flow rates from 8.75 to 25 feet per minute and bed heights from 5 to 12 inches, resulted in filtration efficiencies ranging from about 50 to 90 percent. Removal efficiency of the fluidized bed improved with increased bed height and decreasing superficial gas flow velocities. Analysis of filtration mechanisms indicated that inertial impaction forces may be considered negligible and that the predominant effects are Brownian diffusion, direct interception and induced electrostatic attraction. An equation is presented describing effective filtration efficiency as a function of mean sizes of challenging aerosol and bed material, air viscosity and density, bed height-to-diameter ratio, and superficial gas flow velocity. Analyses and tests indicated particulate approximately 0.5 micron in diameter to be the most difficult to remove from the air stream by use of the fluidized bed. Filtration efficiencies were found for both larger and smaller particles. |
Genre | Thesis/Dissertation |
Topic | Air filters |
Identifier | http://hdl.handle.net/1957/47529 |