To attain high distillation tray efficiency, operators must ensure___________________?
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Answer: A. Interfacial surface between liquid and gas phase should be large
Explanation
Tray efficiency improves when vapor and liquid have extensive contact area for mass transfer. A large interfacial surface area accelerates the rate of component transfer between phases. Maximizing contact area ensures that vapor-liquid equilibrium is closely approached on every tray. Distillation tray efficiency measures how closely a real tray approaches theoretical equilibrium. Mass transfer rates depend directly on the contact area available between phases. Perforations and valve designs on trays are engineered to promote intensive bubble formation.
Industrial chemical plants require high tray efficiency to reduce total column height requirements. Optimizing tray design minimizes capital expenditure and operating energy costs significantly. Petroleum fractionators rely on efficient vapor-liquid contacting for high purity products. Shorter contact times reduce the extent of mass transfer and lower overall tray efficiency. Extremely low gas velocities fail to adequately aerate the liquid pool on the tray. Severe liquid entrainment carries impure liquid upwards, severely degrading separation efficiency.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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