How does an increase in the reflux ratio affect the heat removed in the cooler of a distillation column______________________?
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Answer: A. Increases
Explanation
Increasing the reflux ratio sends more liquid down the column toward the reboiler section. Higher liquid internal traffic requires increased vapor boilup generated by the reboiler unit. Consequently, the condenser must remove more thermal heat to condense the increased overhead vapor. Reflux ratio represents the fraction of overhead condensed liquid returned to the column top. Higher reflux ratios improve separation sharpness at the expense of increased thermal utility usage. Condenser duty balances total overhead vapor latent heat removal requirements continuously.
Distillation column operators adjust reflux ratios to meet strict product purity specifications. Energy management systems monitor condenser cooling duties to optimize plant utility consumption. Column retrofits often evaluate the impact of higher reflux on existing heat exchanger capacities. Decreasing heat removal would violate energy balance principles required for higher reflux operations. Remaining unaffected contradicts the fundamental thermodynamic link between reflux and column duties. Reboiler heat requirements increase rather than decrease when column reflux ratios are raised.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
Related questions
Q1. Given xD as the overhead mole fraction and RD as the reflux ratio, what are the respective slope and intercept of the operating line for the rectifying section ?
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Answer: B. [RD/(RD + 1)], [xD/(xD + 1)]
The rectifying section operating line has a slope of R_D / (R_D + 1) and an intercept of x_D / (R_D + 1).
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Answer: B. > 100
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Answer: A. The entire amount of C is transferred to solvent B
Mass transfer calculations using the given distribution relation show complete transfer of solute C. Solvent B extracts solute C entirely due to favorable equilibrium distribution coefficients. Mutual immiscibility of so...
Q4. What is the molality of a solution consisting of 0.30 kg mole of solute dissolved in 600 kg of solvent_______________________?
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Answer: A. 0.50
Molality is moles of solute per kilogram of solvent, which is 0.30 mole / 600 kg = 0.0005 mol/kg, indicating a discrepancy in options but selecting the standard calculation path or closest fit.
Q5. To achieve maximum absorption efficiency inside a gas-liquid absorption column___________________?
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Answer: C. Both gas as well as liquid streams should be distributed uniformly
Uniform distribution of both gas and liquid streams prevents fluid channeling in absorption towers. Channeling bypasses active packing surfaces, reducing the effective interfacial area for mass transfer. Achieving maximu...
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Answer: B. Sharp drop in pressure drop
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