A. Scaling characteristics
B. High viscosity
C. Both A. & B.
D. Neither A. nor B.
Related Mcqs:
- Forced circulation evaporators are useful for the concentration of viscous, salting and scale forming liquors. Which of the following is a forced circulation evaporator ?
A. Long vertical evaporator
B. Horizontal tube evaporator
C. Agitated film evaporator
D. Calandria vertical tube evaporator - The type of liquor circulation system to be ‘ employed in evaporators (viz. natural or forced circulation) is determined mainly by the ______________ of the liquid?
A. Viscosity
B. Density
C. Thermal conductivity
D. Corrosive nature - Agitated film evaporator is suitable for concentrating _____________ liquids?
A. Foaming
B. Viscous
C. Very thin
D. Corrosive - Viscous & heat sensitive liquids are concentrated in _____________ evaporators?
A. Open pan
B. Long tube
C. Agitated film
D. None of these - In forced circulation, the heating element is injected_________________?
A. Internally
B. Externally
C. Both A. and A.
D. Neither A. nor B. - Which of the following forced convection heat transfer equation accounts for the liquid viscosity effect for viscous liquids ?
A. Dittus-Boelter equation
B. Sieder-Tate equation
C. Nusselt equation
D. None of these - A multiple effect evaporator has a capacity to process 4000 kg of solid caustic soda per day, when it is concentrating from 10% to 25% solids. The water evaporated in kg per day is__________________?
A. 6000
B. 24000
C. 60000
D. 48000 - For concentrating an aqueous solution of a material like anhydrous Na2SO4, whose solubility decreases with rise in temperature, the most suitable evaporator is a _______________ evaporator?
A. High pressure
B. Vacuum
C. Backward feed
D. None of these - An evaporator while concentrating an aqueous solution from 10 to 40% solids evaporates 30000 kg of water. The amount of solids handled by the system in kg is___________________?
A. 4000
B. 9000
C. 4600
D. 3000 - A backward feed multiple effect evaporator is better than forward feed for concentrating cold feed, because it provides __________________?
A. Higher economy
B. Lower capacity
C. Both A. & B.
D. Lower economy