A. Is computed from the slope of the upper operating line that is tangent to the equilibrium curve
B. Is computed from the intercept of the operating line
C. Cannot be computed
D. Is the optimum reflux ratio
Related Mcqs:
- In a distillation operation, what is the effect of the temperature of the reflux stream (given below) on the condenser and reboiler loads? Reflux conditions: (i) Reflux stream is completely liquid and is at its bubble point. (ii) Reflux stream is below its bubble point ?
A. Condenser and reboiler loads are the same in both the cases
B. Reboiler load is the same in both the cases but condenser load is higher in case (ii)
C. Condenser load is the same in both the cases but reboiler load is higher in case (ii)
D. Both condenser and reboiler loads are higher in case (ii) as compared to case (i) - If Rm is the minimum reflux ratio, the optimum reflux ratio may be around _________________ Rm ?
A. 1.2 to 1.5
B. 2.5 to 3
C. 3 to 4
D. 5 - The reflux to a distillation column is 100 moles/hr, when the overhead product rate is 50 moles/hr. The reflux ratio is____________________?
A. 2
B. 0.5
C. 50
D. 150 - Pick out the correct relationship. (Where, Ri = internal reflux ratio Ro = external reflux ratio.) ?
A. (1 + Ro) = Ro/Ri
B. (1 – Ro) = Ro/Ri
C. (1 + Ri) = Ro/Ri
D. (1 – Ri) = Ro/Ri - In continuous distillation, the internal reflux ratio (Ri) and the external reflux ratio (Re) are related as_____________________?
A. Ri = Re/(1 – Re)
B. Ri = (1 – Re)/Re
C. Ri = Re
D. Ri = Re/(1 + Re) - What is the reflux ratio at total reflux ?
A. Zero
B. Infinity
C. Unity
D. Data insufficient - For ethanol-water system, the lowering of distillate quality from 95% to 92% will cause ______________ plate requirement?
A. No change in theoretical
B. Marginal decrease in the number of
C. Major decrease in the number of
D. None of these - For ethanol-water system, the lowering of distillate quality from 95% to 92% will cause ____________________ plate requirement?
A. No change in theoretical
B. Marginal decrease in the number of
C. Major decrease in the number of
D. None of these - The operating cost of a distillation column at minimum reflux ratio is____________________?
A. Minimum
B. Maximum
C. Infinite
D. Zero - At minimum reflux ratio for a given separation__________________?
A. Number of plates is zero
B. Number of plates is infinity
C. Minimum number of the theoretical plates is required
D. Separation is most efficient
