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Home Chemical Engineering Process Equipment and Plant Design Comments

  • Question
  • The LMTD correction factor (FT) is applied in __________ heat exchangers.


  • Options
  • A. 1-1 cocurrent
  • B. double pipe
  • C. all multipass
  • D. all (involving liquid/liquid heat transfer)

  • Correct Answer
  • all multipass 


  • Process Equipment and Plant Design problems


    Search Results


    • 1. High pressure fluid in a shell and tube heat exchanger should preferably be routed through the

    • Options
    • A. tubes to avoid the expansion of high pressure shell construction.
    • B. shell side for smaller total pressure drop.
    • C. shell side, if the flow is counter-current and tube side if the flow is co-current.
    • D. shell side for large overall heat transfer co-efficient.
    • Discuss
    • 2. Low pressure steam (with saturation temperature between 105 to 120°C) is usually used in the vacuum evaporators, which normally employ a vacuum of about __________ mm Hg (referred to a 760 mm mercury barometer).

    • Options
    • A. 250
    • B. 450
    • C. 650
    • D. 750
    • Discuss
    • 3. Brass valves are usually made for pipe sizes __________ inches.

    • Options
    • A. ?1
    • B. ?2
    • C. >2.5
    • D. >3.5
    • Discuss
    • 4. In actual operation of distillation column, the vapour is not distributed uniformly among the bubble caps, primarily because of the

    • Options
    • A. liquid gradient on the tray.
    • B. lower skirt clearance.
    • C. lower static submergence.
    • D. small downcomer liquid seal.
    • Discuss
    • 5. Tube wall thickness depends on the cor-rosiveness of the fluids and their operating pressure & temperature and is specified by Birmingham wire gauge (B.W.G)-a number which varies from 8 to 18 with the numbers 14 and 16 being more commonly used. Outside diameter of tubes varies from about 15 to 50 mm; however a tube of less than __________ mm outside diameter is generally not recommended for fouling fluids.

    • Options
    • A. 16
    • B. 19
    • C. 28
    • D. 38
    • Discuss
    • 6. The minimum shell thickness for tank ? 15 metres diameter is limited to __________ mm, for reasons of elastic stability.

    • Options
    • A. 2
    • B. 5
    • C. 10
    • D. 15
    • Discuss
    • 7. In a shell and tube heat exchanger, the clearance of the tube is generally

    • Options
    • A. not less than one-fourth of the tube diameter or 3/16".
    • B. more than the tube diameter.
    • C. equal to the tube diameter.
    • D. more in case of triangular pitch as compared to the square pitch tube layout.
    • Discuss
    • 8. For annular flow of a fluid, the ratio of the equivalent diameter for pressure drop calculation to the equivalent diameter for heat transfer calculation is

    • Options
    • A.
    • B.
    • C.
    • D.
    • Discuss
    • 9. In a shell and tube heat exchanger, the overall heat transfer co-efficient is proportional to the tube side (volumetric flow rate)0.8. This is valid, only when the ratio of the tube side film resistance to the total resistance is almost equal to

    • Options
    • A. ?
    • B. 1
    • C. 20.8
    • D. 2
    • Discuss
    • 10. Pick out the wrong statement pertaining to the design of a horizontal tube evaporator.

    • Options
    • A. It is unsuitable for concentrating those liquids, which form a scale or deposit salt.
    • B. It is suitable for process, in which the final product is a liquor instead of solid.
    • C. Its usual dimensions are: tube dia = 2-3 cms; evaporator body dia = 1-4 metres and evaporator height = 2.5-4 metres.
    • D. Liquor flows inside the tube, while the steam is outside submerging the tube.
    • Discuss


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