Nonspherical particles in a pseudo-2D fluidized bed: Experimental study

Area of Science:

• Chemical Engineering
• Particle Technology

Background:

• Fluidization is a key industrial process, extensively studied.
• Most research focuses on spherical particles, neglecting real-world non-spherical granules.
• Particle shape critically influences fluidization dynamics.

Purpose of the Study:

• To investigate the fluidization behavior of non-spherical, rod-like particles.
• To characterize the impact of particle shape on fluidization characteristics.
• To compare experimental results with existing pressure drop correlations for nonspherical particles.

Main Methods:

• Experiments conducted in pseudo-2D fluidized beds.
• Utilized pressure drop measurements.
• Employed optical methods: Digital Image Analysis (DIA), Particle Image Velocimetry (PIV), and Particle Tracking Velocimetry (PTV).

Main Results:

• Rod-like particles (aspect ratio 4) demonstrated interlocking and channeling.
• Observed vigorous bubbling fluidization with particle ejection and dispersion.
• Identified a central upward and wall downward circulation pattern at high flow rates.
• Measured bed height, particle orientation, circulation, stacking, and coordination number.

Conclusions:

• Particle shape, specifically rod-like geometry, introduces complex behaviors like interlocking not seen with spheres.
• Existing pressure drop correlations may not accurately predict fluidization for such nonspherical particles.
• Understanding these shape-dependent phenomena is crucial for optimizing industrial fluidization processes.