Basic filtration mechanisms and pertinent parameters in the filtration of aerosols by fixed and fluidized granular beds was studied to determine the feasibility of using such beds as high efficiency particle collection devices. Beds of plastic beads (polyacrylonitrile), 305 and 495 micrometers in diameter, and beds of sand, 680 micrometers in diameter were employed in 10.16 cm (4 in) diameter Lucite columns to collect small aerosol particles. Bed penetration was determined as a function of several variables: bed granule size, bed height (3, 6, and 9 cm) superficial gas velocity (3.1-18.5 cm/sec), flow direction (upflow vs. downflow), and aerosol particle size. The pressure drop across the beds was also measured. Results indicate that high collection efficiencies (low bed penetrations) (99 percent or better) can be obtained with relatively shallow (9 cm or less) fixed and fluidized beds of plastic beads.
- Pub Date:
- Fluidized Bed Processors;
- Beds (Process Engineering);
- Particle Size Distribution;
- Fluid Mechanics and Heat Transfer