Minimum liquid fluidization velocity in gas-liquid-solid fluidized beds
- Univ. of Western Ontario, London, Ontario (Canada). Dept. of Chemical and Biochemical Engineering
Accurate detection of minimum liquid fluidization is essential to the successful operation of gas-liquid-solid fluidized beds, especially when particle or liquid properties evolve. A gas-liquid-solid system of 3-mm glass beads exhibits three distinct flow regimes as the liquid velocity is increased: compacted, agitated and fluidized-bed regimes. Measurements showed that the bed is not fluidized in the agitated bed regime. Pressure gradient and bed height measurements do not provide the minimum liquid fluidization velocity; instead, they offer the velocity between the compacted and agitated bed regimes. Time-averaged signals are not reliable for determining the minimum liquid fluidization velocity. It can be obtained from the standard deviation, the average frequency, the Hurst exponent and the V statistic of the cross-sectional average conductivity, which can be measured under many industrial conditions. Examples of applications of gas-liquid-solid fluidized bed reactors include coal liquefaction and petroleum hydrotreating.
- Sponsoring Organization:
- Natural Sciences and Engineering Research Council of Canada, Ottawa, ON (Canada)
- OSTI ID:
- 506007
- Journal Information:
- AIChE Journal, Vol. 43, Issue 5; Other Information: PBD: May 1997
- Country of Publication:
- United States
- Language:
- English
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