Measuring and modeling solids movement in a large, cold fluidized-bed test facility. Final report
Solids movement in a large-particle fluidized bed was studied in an 18 in x 18 in (46 cm x 46 cm) tube-filled, cold fluidized-bed test facility. Direct measurement of local solid mass flux in two dimensions at various locations inside the bed was made possible by a new instrument developed in this study. This instrument can be installed as a part of the bed internal tube array and hence does not interfere with the solid flow field being measured. The instrument makes use of the magnetic property of solid and requires a bed media consisting entirely of magnetic solid particles. Iron particles with a mean particle diameter of 0.032 in (0.8 mm) and a density of 387 lb/ft/sup 3/ (6200 kg/m/sup 2/) were used. Experiments were conducted at room temperature and atmospheric pressure with air as the fluidizing gas. Two gas velocities above the minimum fluidizing velocity were used. The net local solid movement and the gross solid circulation pattern inside the bed were deduced from the vertical and one horizontal component of the local solid mass fluxes measured at various locations inside the bed. Two specific solid flow regions were found to exist. The net solids movement in the middle bubbling region of the bed was in the upward direction while adjacent to the bed walls the net solid movement was downward. The net lateral solid movement was not significant in the bubbling region of the bed. However, at the bottom of the bed this movement can be significantly enhanced by means of an uneven gas velocity distribution inside the bed. A theoretical model for the gross solid circulation observed in a freely bubbling fluidized bed is proposed.
- Research Organization:
- Oregon State Univ., Corvallis (USA). Dept. of Chemical Engineering
- DOE Contract Number:
- AC01-79ET13152
- OSTI ID:
- 6128218
- Report Number(s):
- DOE/ET/13152-T2; ON: DE83010952
- Resource Relation:
- Other Information: Portions are illegible in microfiche products. Original copy available until stock is exhausted
- Country of Publication:
- United States
- Language:
- English
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