A. Scaling
B. Highly viscous
C. Corrosive
D. Salty
Related Mcqs:
- It is desired to concentrate a 20% salt solution (20 kg of salt in 100 kg of solution) to a 30% salt solution in an evaporator. Consider a feed of 300 kg/min at 30°C. The boiling point of the solution is 110°C, the latent heat of vaporisation is 2100 kJ/kg and the specific heat of the solution is 4 kJ/kg.K. The rate at which the heat has to be supplied in (kJ/min) to the evaporator is____________________?
A. 3.06 × 105
B. 6.12 × 105
C. 7.24 × 105
D. 9.08 × 105 - Boiling point elevation for a strong and concentrated solution is found by Duhring’s rule, which states that at the same pressure, the boiling point of a solution is a linear function of the _______________ of pure water?
A. Boiling point
B. Dynamic viscosity
C. Kinematic viscosity
D. Density - Viscous & heat sensitive liquids are concentrated in _____________ evaporators?
A. Open pan
B. Long tube
C. Agitated film
D. None of these - A dilute aqueous solution is to be concentrated in an evaporator system. High pressure steam is available. Multiple effect evaporator system is employed, because__________________?
A. Total heat transfer area of all the effects is -less than that in a single effect evaporator system
B. Total amount of vapor produced per Kg of feed steam in a multiple effect system is much
higher than in a single effect
C. Boiling point elevation in a single effect system is much higher than that in any effect in a
multi-effect system
D. Heat transfer co-efficient in a single effect is much lower than that in any effect in a multieffect
system - Which is the most suitable for the concert-ration of highly concentrated solution ?
A. Open pan evaporation
B. Long tube vertical evaporator
C. Agitated film evaporator
D. None of these - For evaporation of viscous solution in a multiple effect evaporator, the preferred feeding scheme is _________________?
A. Forward
B. Backward
C. Parallel
D. None of these - In case of a super-cooled solution, which is on the verge of crystallisation, the free energy of the solution as compared to that of the solid is ________________?
A. More
B. Less
C. Same
D. More or less; depends on the nature of solution - In case of evaporators, liquid entrainment results primarily due to_________________?
A. High vacuum in the evaporator
B. High evaporation rate
C. Foaming of the solution
D. High heat transfer rate - In evaporators, lowering the feed temperature_______________?
A. Increases the heating area required
B. Reduces the economy
C. Both A. and B.
D. Decreases the heating area required - The advantage of backward feed multiple effect evaporators over forward feed units is that___________________?
A. Heat sensitive material can be handled
B. There is no additional cost of pumping
C. Most concentrated liquid is at highest temperature
D. Equal heat transfer co-efficients exist in various effects
