What is the steam economy in case of a single effect evaporator system ?

Related Mcqs:

1. In a single evaporator system, the steam economy ________________ by creating vacuum in the evaporator?

   A. Increases
   B. Decreases
   C. Remain constant
   D. May increase or decrease, depends on the vacuum

2. Steam consumption in kg/hr in case of an evaporator is given by (where, C & E are capacity the economy of the evaporator respectively) ?

   A. C/E
   B. E/C
   C. CE
   D. 1/CE

3. A multiple effect evaporator as compared to a single effect evaporator of the same capacity has _________________?

   A. Lower heat transfer area
   B. Lower steam economy
   C. Higher steam economy
   D. Higher solute concentration in the product

4. For the same heat transfer area and the terminal conditions, the ratio of the capacities of a single effect evaporator to a triple effect evaporator is_________________?

   A. 3
   B. 0.33
   C. 1
   D. 1.33

5. Steam economy in case of a triple effect evaporator will be _________________?

   A. 1
   B. < 1
   C. > 1
   D. Between 0 and 1

6. 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

7. In a single effect evaporator, the economy is________________?

   A. 1
   B. < 1
   C. > 1
   D. None of these

8. Evaporation of 1kg of water from a solution in a single effect evaporator requires about ________________ kg of steam?

   A. 0.4 – 0.6
   B. 1-1.3
   C. 1.8-2
   D. 2 – 2.4

9. Economy of a multiple effect evaporator depends upon the _____________________?

   A. Heat balance consideration
   B. Rate of heat transfer
   C. Both A. and B.
   D. Neither A. nor B.

10. Economy of a multiple effect evaporator is not influenced much by the_______________________?

    A. Boiling point elevations
    B. Temperature of the feed
    C. Rate of heat transfer
    D. Ratio of the weight of the thin liquor to thick liquor