Study of Defluidization Region of Large Particles in Fluidized Bed Using the Gaussian Spectral Pressure Distribution

Abstract:

The present work aimed to identify the defluidization region of a gas-solid fluidized bed system composed by Geldart group D particles using the Gaussian spectral pressure distribution technique, which is based on pressure fluctuation measurements in the plenum. In experiments, the defluidization condition of glass beads with apparent density of 2,450 kg/m³ was induced in a plexiglas column of 0.11 m in inner diameter and 1.0 m in height. The gas-solid behavior close to the incipient fluidization condition was assessed for two fixed bed heights (0.10 and 0.20 m) and two mean sizes of particles (1.55 and 2.18 mm in diameter). The bed was fluidized with air at environment temperature. The experimental equipment was instrumented with a pressure transmitter connected to a data acquisition system in order to record the pressure fluctuations of the gas-solid flow. The results showed that the defluidization region can be detected efficiently by using the Gaussian spectral pressure distribution technique, which contributes for a better control of fluidized bed processes.

• Periodical: Advanced Materials Research (Volume 1104)
• Pages: 69-74
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1104.69
• Online since: May 2015
• Authors: Flavia Tramontin Silveira, Frederic Conrad Janzen, Maria Regina Parise*
• Keywords: Defluidization, Gas Solid Fluidized Bed, Gaussian Spectral Pressure Distribution, Pressure Measurements, Signal Analysis

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