Abstract
In a 9.3 m high and 0.10 m i.d. gas-solids downflow fluidized bed (downer), the radial distributions of the local solids holdups and the pressure gradients along the downer column were measured to characterize the local and overall gas-solid low structure, using a fiber optical solids concentration probe and a series of pressure transducers. Results show that the radial solids holdup distribution in a downer reactor is much more uniform than that in a riser. Although the operating conditions do largely affect the hydrodynamics in the downer reactor, many common similarities still exist in the gas-solids flow patterns with the variation of the operating conditions. For most of the conditions tested, the radial profile of solids holdup reaches its fully developed state within 3-8 m from the top entrance. On the other hand, particles are fully accelerated within 1-4 m. However, under certain conditions, the development section can extend to as long as the downer itself.
Original language | English |
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Pages (from-to) | 5461-5470 |
Number of pages | 10 |
Journal | Chemical Engineering Science |
Volume | 54 |
Issue number | 22 |
DOIs | |
Publication status | Published - Nov 1999 |
Externally published | Yes |
Keywords
- Downer reactor
- Flow development
- Fluidized bed
- Gas-solids cocurrent downflow
- Hydrodynamics
ASJC Scopus subject areas
- General Chemistry
- General Chemical Engineering
- Industrial and Manufacturing Engineering