What is the primary factor influencing the behavior of fluidized solid beds___________________?
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Answer: C. Both A. and B.
Explanation
Fluidized bed hydrodynamics depend on both fluid properties and solid particle characteristics. Fluid viscosity and density dictate drag forces acting on individual suspended particles. Particle size, shape, and density determine terminal settling velocities and bed expansion. Fluidization occurs when upward flowing fluid suspends a bed of solid particles. Minimum fluidization velocity marks the threshold where pressure drop balances particle weight. Heterogeneous and homogeneous fluidization regimes depend heavily on phase interactions.
Chemical reactors utilize fluidized beds to achieve excellent mixing and rapid heat transfer. Catalytic cracking units in petroleum refineries rely on continuous solids fluidization. Coal gasification and drying processes require precise control of gas and particle properties. Focusing solely on fluid characteristics ignores the crucial role of particle geometry. Considering only particle size neglects fluid viscosity and density effects on drag. Option neither is incorrect because both fluid and particle properties govern behavior.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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