Column plate efficiency diminishes as a result of excessive ______________________ of liquid across plates?
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Answer: D. All A., B. & C.
Explanation
Plate efficiency suffers when excessive liquid entrainment, foaming, weeping, or dumping occurs. These hydrodynamic abnormalities disrupt proper vapor-liquid contacting on every tray. Mass transfer between phases is severely impaired, lowering overall column efficiency. Distillation tray columns rely on stable hydraulic operation for efficient separation. Entrainment carries liquid upward, while weeping causes liquid to leak downward prematurely. Foaming fills inter-tray spaces and leads to liquid carryover and flooding.
Plant operators adjust boilup rates to maintain stable column hydraulics without flooding. Tray design parameters prevent weeping and dumping during turndown operations. Monitoring pressure drop helps identify when hydrodynamic limits are being approached. Entrainment alone reduces efficiency, but weeping and foaming contribute equally. Foaming causes operating instability and efficiency loss alongside entrainment. Option D correctly includes all listed phenomena that degrade column efficiency.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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